NIST Handbook 112 (2015)

EPO No. 9, Part 1 – Monorail Scales – Electronic Digital Indicators

Monorail Scales (Rev 09/14) DRAFT Page 1 of 16

2015 NIST EPO No. 9

Examination Procedure Outline for

Part 1 – Monorail Scales – Electronic Digital Indicators

Part 1 – Monorail Scales – Electronic Digital Indicators ..........................................................1

Part 2 – Monorail Scales and Meat Beams – Mechanical .......................................................11

It is recommended that this outline be followed as minimum criteria for examining monorail scales equipped with 

electronic digital indicators used to weigh statically or dynamically. See EPO 9, Part 2 for Mechanical Meatbeam

and Monorail Scales. 

Requirements that apply only to scales marked with an accuracy class are indicated with an asterisk. Nonretroactive 

requirements are followed by the applicable date in parentheses.

SAFETY NOTES

When excerpting this Examination Procedure Outline for duplication, the EPO Safety Annex (Safety 

Considerations and Glossary of Safety Key Phrases) should be duplicated and included with this outline.

Safety policies and regulations vary among jurisdictions. It is essential that inspectors or servicepersons be 

aware of all safety regulations and policies in place at the inspection site and practice their employer’s safety 

policies. The safety reminders included in this EPO contain general guidelines useful in alerting inspectors and 

servicepersons to the importance of taking adequate precautions to avoid personal injury. These guidelines can 

only be effective in improving safety when coupled with training in hazard recognition and control. 

Prior to beginning any inspection, the inspector should read and be familiar with the EPO Safety Annex - “Safety 

Considerations and Glossary of Safety Key Phrases." The terms and key phrases in each safety reminder of this 

outline are found in the glossary of the EPO Safety Annex. The inspector is reminded of the importance of 

evaluating potential safety hazards prior to an inspection and taking adequate precautions to avoid personal injury or 

damage to the device. As a minimum, the following safety precautions should be noted and followed during the 

inspection:

Clothing Personal Protection Equipment

e.g., Safety Shoes

Electrical Hazards Support – for scales, test weights, and load-receiving 

elements (e.g., meat hooks or test platform)

First Aid Kit Transportation of Equipment

Hardhat – for protection from overhead (e.g., 

hanging meat hooks)

Eye Protection - for protection from hanging meat hooks

Lifting

Also: Overhead Hazard, Materials or Obstructions
NIST Handbook 112 (2015)

EPO No. 9, Part 1 – Monorail Scales – Electronic Digital Indicators

Page 2 of 16 Monorail Scales (Rev 09/14) DRAFT

H-44 General Code and 

Scale Code References

Inspection:

SAFETY REMINDER!!!

− Check the inspection site carefully for safety hazards and take appropriate precautions.

− Learn the nature of hazardous products used at or near the inspection site.

− Use personal protection equipment appropriate for the inspection site.

− Be sure that a first aid kit is available and that the kit is appropriate for the type of inspection 

activity.

1. Zero-load balance as found. ...........................................................................................

If the device is not in balance, the user should be made aware of paragraph 

UR.4.1., and warning issued if necessary. If device is set for tare, check 

accuracy of the tare being taken.

S.1.1., S.1.1.1., S.2.1.1., 

S.2.1.2., S.2.1.4., UR.4.1., 

G-S.5.2.2(d)*

2. Indicating and recording elements.

Scale division, value (d) and number (n). ...............................................................

Tare division value...................................................................................................

Tare mechanism. ......................................................................................................

Appropriateness. ......................................................................................................

Recording elements, General ...................................................................................

Customer readability, if applicable. .........................................................................

Damping means. ......................................................................................................

Adjustable components. ...........................................................................................

Provision for sealing. ...............................................................................................

Manual Weight Entries. ...........................................................................................

S.1.2.*, S.1.2.1. (1/1/89), 

S.1.2.2., S.5.*, 

G-UR.1.1., UR.1., 

UR.1.1.(b), G-S.5.3., 

UR 1.3.1.(b), UR.3.10.

S.2.3. (1/1/83), S.2.3.1.

S.2.3.

G-S.5., S.1.7., 

S.5.2.*,UR.1.1. (a)*, 

UR.3.1.*

G-S.5.6.

G-UR.3.3.

S.2.5.1.

S.1.10.

S.1.11. (1/1/90), 

G-UR.4.5., G-S.8.

G-S.8.1. (1/1/2010)

S.1.12. (1/1/93), UR.3.9.

S.6.3., S.6.2.
NIST Handbook 112 (2015)

EPO No. 9, Part 1 – Monorail Scales – Electronic Digital Indicators

Monorail Scales (Rev 09/14) DRAFT Page 3 of 16

H-44 General Code and 

Scale Code References

Inspection (cont.):

3. Marking. .........................................................................................................................

a. Marking requirements - all devices

Identification.................................................................................................

Name or ID of manufacturer.........................................................................

Model identifier............................................................................................

Model identifier prefix..................................................................................

Nonrepetitive serial number. ........................................................................

Serial number prefix. ....................................................................................

NTEP CC prefix and number (for devices that have an NTEP CC).............

Software version or revision identifier. .......................................................

Devices or main elements remanufactured after January 1, 2002. ...............

name and ID of remanufacturer or distributor...........................................

model number if different from original model number. ..........................

G-S.1.

Retroactive

Retroactive

(1/1/03)

(1/1/68)

(1/1/86)

(1/1/03)

(1/1/04)

G-S.1.2.

G-S.1. 

(1/1/02)

(1/1/02)

b. Marking requirements - weighing and indicating elements in same housing 

or covered on the same CC (in addition to marking for all devices)..................

Accuracy class..................................................................................................

Nominal capacity. ............................................................................................

Value of scale division with nominal capacity, if not apparent........................

Value of "e" (if different from "d"). .................................................................

Temperature limits if narrower than and within − 10 °C to 40 °C (14 °F to 

104 °F). .....................................................................................................

Scales designed for special purposes.

c. Marking requirements - indicating element not permanently attached or 

covered on separate CC (in addition to marking for all device). .......................

Accuracy class..................................................................................................

Nominal capacity. ............................................................................................

Value of scale division with nominal capacity, if not apparent........................

Value of "e" (if different from "d"). .................................................................

Temperature limits if narrower than and within -10 °C to 40 °C (14 °F to 

104 °F). .....................................................................................................

Scales designed for special purposes................................................................

Maximum number of scale divisions (nmax). ....................................................

d. Marking requirements for weighing and load-receiving element not 

permanently attached or covered on separate CC (in addition to marking for 

all devices). ........................................................................................................

Accuracy class..................................................................................................

Nominal capacity. ............................................................................................

Temperature limits if narrower than and within -10 °C to 40 °C (14 °F to 

104 °F). .....................................................................................................

Scales designed for special application. ...........................................................

Maximum number of scale divisions (nmax)...................................................

Minimum verification scale division for which device complies with the 

requirements (emin or d).............................................................................

e. Marking requirements - load cell with Certificate of Conformance (in 

addition to marking for all devices)...................................................................

S.6.3. 

(1/1/86)

Retroactive

(1/1/83)

(1/1/86)

(1/1/86)

(1/1/86)

S.6.3.

(1/1/86)

Retroactive

(1/1/83)

(1/1/86)

(1/1/86)

(1/1/86)

(1/1/88)

S.6.3.

(1/1/86)

Retroactive

(1/1/86)

(1/1/86)

(1/1/88)

(1/1/88)

S.6.3., S.5.4. (1/1/94)
NIST Handbook 112 (2015)

EPO No. 9, Part 1 – Monorail Scales – Electronic Digital Indicators

Page 4 of 16 Monorail Scales (Rev 09/14) DRAFT

H-44 General Code and 

Scale Code References

Inspection (cont.):

G-S.1. (cont.)

Note: Requires information on a data plate attached to the load cell or in 

accompanying document. If a document is provided, the serial number shall

appear on the load cell and in the document. ...................................................

Manufacturer’s name or trademark, model designation, model prefix, and 

serial number and prefix shall also be marked on both the load cell and 

in any accompanying documents. .............................................................

Accuracy class..................................................................................................

Temperature limits if narrower than and within − 10 °C to 40 °C (14 °F to 

104 °F). .....................................................................................................

Maximum number of divisions. .......................................................................

“S” or “M” for single or multiple cell applications..........................................

Direction of loading, if not obvious. ................................................................

Minimum dead load, maximum capacity, safe load limit, and load cell 

verification interval, Vmin. .........................................................................

(1/1/88)

(1/1/91)

(1/1/86)

(1/1/86)

(1/1/88)

(1/1/88)

(1/1/88)

(1/1/88)

f. Marking requirements – current software version or revision identifier for 

not built-for-purpose, software- based devices. .................................................G-S.1.(d) (1/1/2004), 

G-S.1.(d)(1)(2), (1/1/07), 

G-S.1.1.(1/1/2004)

4. Design of balance, tare, level, damping, and arresting mechanisms. .............................S.2.1., S.2.3., S.2.5.1.

5. Design of weighing elements. ........................................................................................S.4.

6. Installation : 

Static monorail scales..............................................................................................

Dynamic monorail scale considerations:.................................................................

− Space to avoid contact between carcasses,

− Higher resolution checkweigh scales, and 

− Carcasses used multiple times.

UR.2.3., UR.2.4., 

G-UR.2.

N.1.3.5.1., UR.2.3., 

UR.2.4., G-UR.2.
NIST Handbook 112 (2015)

EPO No. 9, Part 1 – Monorail Scales – Electronic Digital Indicators

Monorail Scales (Rev 09/14) DRAFT Page 5 of 16

H-44 General Code and 

Scale Code References

Inspection (cont.):

SAFETY REMINDER

− Check the inspection site carefully for safety hazards and take appropriate precautions.

− Use caution in moving in wet, slippery areas.

− Use personal protection equipment appropriate for the inspection site.

− Be sure that a first aid kit is available and that the kit is appropriate for the type of 

inspection activity.

− Check to be sure the scale supports are adequate to support the scale, test weights equal to 

the capacity of the scale, and test platforms or chains to suspend test weights

7. Maintenance, use, and environmental factors (cleanliness, obstructions, modifications, 

etc.)...................................................................................................................................G-S.2., G-UR.1.2., 

G-UR.3.1., G-UR.3.2., 

G-UR.4., UR.4.3.

8. Assistance.......................................................................................................................G-UR.4.4.

9. Provisions for testing and accessibility...........................................................................UR.2.9., G-UR.2.3.

10. Determination of Load Cell Suitability (applicable to load cells with an NTEP 

Certificate of Conformance): 

a. The number of scale divisions (n) of the scale is less than or equal to the nmax 

of the indicator or the load cells, whichever is less; for example, if the 

indicator has an nmax of 10 000 and the load cells have an nmax of 5000, then 

the scale may use up to 5000 divisions.

b. The load cell is approved for the required accuracy class. Note: A Class II 

load cell may be used in a Class III application; however the opposite is not 

true.

c. The load cell is rated Single (S) or Multiple (M) use as appropriate to the 

application.

Note: A load cell rated for single use may be used in a single or multiple load cell 

application; however, a load cell rated for multiple uses cannot be used in a single 

load cell application.

d. The load cell complies with the requirements for Vmin and temperature effect 

on zero-load balance. .........................................................................................S.5.4., T.N.8.1.3.
NIST Handbook 112 (2015)

EPO No. 9, Part 1 – Monorail Scales – Electronic Digital Indicators

Page 6 of 16 Monorail Scales (Rev 09/14) DRAFT

H-44 General Code and 

Scale Code References

Inspection (cont.):

For scales with mechanical lever systems:

*When the value of the scale division, d, is different from the verification scale 

division, e, for the scale, the value of e must be used in the formulae above.

Pretest Determinations:

1. Tolerances.

Acceptance/Maintenance.........................................................................................

Application.......................................................................................................................

Tolerance values:

Scales marked with an accuracy class. ....................................................................

Scales not marked....................................................................................................

Discrimination.........................................................................................................

G-T.1., G-T.2.

T.N.2.1., T.N.2.3., 

T.N.2.4.

T.N.3.1., T.N.3.2., 

Table 6 (Class III), 

T.N.3.8., T.N.4.1., 

T.N.4.4., T.N.4.5., T.N.5.

T.N.7.2.

2. Select trolleys, trees, chains, or other auxiliary gear necessary to suspend test weights 

on rail or meat hook. If two or more trolley-and-tree combinations are used; they 

should be uniform in weight (within plus or minus two ounces).

SAFETY REMINDER!!!

− Wear appropriate personal protection equipment such as hard hats and eye protection to 

prevent injury from overhead meat hooks, hanging carcasses, falling weights, and slipping on 

slick surfaces.

− Wear safety shoes to prevent possible injury from falling weights and slipping on slick surfaces.

lb lb lb

N

d

v 0.71

1.414

1

2

* 1 min ≤ = = =

( )

* min N scalemultipled

v

×

≤
NIST Handbook 112 (2015)

EPO No. 9, Part 1 – Monorail Scales – Electronic Digital Indicators

Monorail Scales (Rev 09/14) DRAFT Page 7 of 16

H-44 General Code and 

Scale Code References

Pretest Determinations (cont.):

3. Minimum test weights and test loads. .......................................................................... N.3.

Test Notes:

1. Suspend auxiliary gear (trolleys, trees, chains) from live rail.

2. Balance in auxiliary gear.

3. Check repeatability and agreement between indications and between indications and 

recorded representations throughout test. .......................................................................T.N.4.1., T.N.5., 

G-S.5.2.2.(a)

4. Verify that any options for obtaining a recorded representation are appropriate. The 

customer may be given the option of not receiving the recorded representation. If the 

system is equipped with the capability, the customer may also be given the option of 

receiving the recorded representation electronically in lieu of or in addition to a hard 

copy. ..............................................................................................................................G-S.5.6.

5. Check zero-load balance each time test load is removed. ..............................................N.1.9., G-UR.4.2

6. If the scale is equipped with a printer, print a ticket at each test load; check

effectiveness of motion detection. ..................................................................................G S.5.6., S.2.5.1., UR.1.3.

(1/1/86)

7. If, during the conduct of the test, the performance of the device is questionable with 

respect to the zone of uncertainty or the width of zero, adequate tests should be 

conducted to determine compliance. ..............................................................................N.1.5., N.1.5.1., S.1.1.1.

8. If the device is equipped with operational features such as automatic zero-setting 

mechanism, programmable tare,*manual weight entries, or two scales with one 

printer, check proper operation and appropriateness.

*Note: See UR.3.9. The use of manual gross weight entries, are not allowed on monorail scales.
NIST Handbook 112 (2015)

EPO No. 9, Part 1 – Monorail Scales – Electronic Digital Indicators

Page 8 of 16 Monorail Scales (Rev 09/14) DRAFT

H-44 General Code and 

Scale Code References

Test:

Static Test:

SAFETY REMINDER!!!

− Wear safety shoes!

− Use proper lifting techniques!

3. RFI/EMI test (if a problem is suspected)........................................................................

Radio Frequency Interference (RFI)

Electromagnetic Interference (EMI)

G-N.2., G-UR.3.2., 

G-UR.4.2., G-UR.1.2., 

N.1.6., T.4., T.N.9.*

4. Over capacity test, if deemed necessary. ........................................................................S.1.7., S.2.1.5., S.2.1.5.(b) 

(1/1/2009)

5. Decreasing load test. Test at one half of maximum test load. .......................................N.1.2.

6. Remove all test weights and determine any zero load balance change. .........................N.1.9., G-UR.4.2.

7. Test for proper design of automatic zero-setting mechanism, if device is so equipped.S.2.1.3.1.(c), S.2.1.3.2.8.

8. If device is equipped with a semi-automatic zero-setting mechanism (push button), 

test effectiveness of motion detection.............................................................................S.2.1.2.(b)

9. Establish correct zero load balance.

Dynamic Test ..................................................................................................................N.1.3.5.1.

On a dynamic test with 20 or more test drafts, 10 % of the individual test drafts may be 

two times the basic tolerances, if the error on the total of all test load drafts does not 

exceed 0.2 %.

1. Conduct dynamic test with livestock carcasses

2. Test no less than 20 test loads using carcasses or portions of carcasses of the type 

normally weighed (two additional test loads may be included in the test run in the 

event that one or two of the test load are rendered unusable).

3. Position the test carcasses far enough ahead of the scale so the swaying motion 

settles to duplicate the normal sway of a continuously running plant chain.
NIST Handbook 112 (2015)

EPO No. 9, Part 1 – Monorail Scales – Electronic Digital Indicators

Monorail Scales (Rev 09/14) DRAFT Page 9 of 16

H-44 General Code and 

Scale Code References

Dynamic Test (cont.)....................................................................................N.1.3.5.1.

4. If the plant conveyor chain does not space or prevent the carcasses from touching 

one another, the dynamic test should not be conducted until this condition is 

corrected.

5. Individually weigh (statistically) the carcasses on the same scale being tested or 

another monorail scale in close proximity with the same or smaller divisions.

a. The scale selected for weighing the carcasses must be tested statically with 

test weights.

6. If the scale being tested is used for weighing freshly slaughtered animals, a static 

weighment of the carcasses must be taken as quickly as possible before or following 

the Dynamic weighment to avoid loss due to shrinkage.

67. If multiple dynamic tests are conducted using the same carcasses, obtain static 

weights before and after multiple dynamic tests. 

8. If the carcass changes weight between static tests, the amount of weight change 

should be taken into account, or the carcass should be discarded for tolerance 

purposes.
NIST Handbook 112 (2015)

EPO No. 9, Part 1 – Monorail Scales – Electronic Digital Indicators

Page 10 of 16 Monorail Scales (Rev 09/14) DRAFT

THIS PAGE INTENTIONALLY LEFT BLANK
NIST Handbook 112 (2015)

EPO – No. 9, Part 2 – Monorail Scales and Meat Beams – Mechanical

Monorail Scales (Rev 09/14) DRAFT Page 11 of 16

2015 NIST EPO No. 9

Examination Procedure Outline for

Part 2 – Monorail Scales and Meat Beams – Mechanical

It is recommended that this outline be followed for monorail scales equipped with equipped with weigh-beams or 

mechanical dials. Requirements that apply only to scales marked with an accuracy class are indicated with an 

asterisk. Nonretroactive requirements are followed by the applicable date in parentheses.

Safety Notes – See EPO 9, Part 1

H-44 General Code 

and Scale Code 

References

Inspection:

SAFETY REMINDER!!!

− Check the inspection site carefully for safety hazards and take appropriate precautions.

− Learn the nature of hazardous products used at or near the inspection site.

− Use personal protection equipment appropriate for the inspection site.

− Be sure that a first aid kit is available and that the kit is appropriate for the type of 

inspection activity.

1. Zero-load balance as found.............................................................................................

If the device is not in balance, the user should be made aware of paragraph 

UR.4.1., and warning issued if necessary. If device is set for tare, check 

accuracy of the tare being taken.

S.1.1., S.2.1.1., S.2.1.2., 

UR.4.1

2. Indicating and recording elements.

Scale division, value (d) and number (n).................................................................

Tare division value. .................................................................................................

Tare mechanism. .....................................................................................................

Weighbeams............................................................................................................

Poises.......................................................................................................................

Dials and balance indicators....................................................................................

Appropriateness................................................................................................

Damping means................................................................................................

Customer readability. .......................................................................................

Adjustable appropriateness. .............................................................................

S.1.2.*, G-UR.1.1., 

UR.1., UR.1.1.(b), 

G-S.5.3.

S.2.3. (1/1/83), S.2.3.1.

S.2.3.

S.1.5. except S.1.5.5.

S.1.6.

S.1.3., S.1.4., S.2.2.

G-S.5., S.1.7., 

UR.1.1.(a),* UR.3.1.,*

S.5.,*UR.3.2.,

S.2.5.
NIST Handbook 112 (2015)

EPO – No. 9, Part 2 – Monorail Scales and Meat Beams – Mechanical

Page 12 of 16 Monorail Scales (Rev 09/14) DRAFT

H-44 General Code 

and Scale Code 

References

Inspection (cont.):

3. Marking. ........................................................................................................................

a. Marking requirements - all devices

Identification. .................................................................................................

Name or ID of manufacturer ..........................................................................

Model identifier..............................................................................................

Model identifier prefix. ..................................................................................

Nonrepetitive serial number. ..........................................................................

Serial number prefix.......................................................................................

NTEP CC prefix and number (for devices that have an NTEP CC)...............

Devices or main elements remanufactured after January 1, 2002. .................

name and ID of remanufacturer or distributor...........................................

Model number if different from original model number..................................

S.6.3., S.6.2.

G-S.1.

Retroactive

Retroactive

(1/1/03)

(1/1/68)

(1/1/86)

(1/1/03)

G-S.1.2.

(1/1/02)

(1/1/02)

b. Marking requirements - weighing and indicating elements in same housing 

or covered on the same CC (in addition to marking for all devices)..................

Accuracy class................................................................................................

Nominal capacity............................................................................................

Value of scale division with nominal capacity, if not apparent......................

Value of "e" (if different from "d"). ..............................................................

Scales designed for special purposes..............................................................

S.6.3.

(1/1/86)

Retroactive

(1/1/83)

(1/1/86)

(1/1/86)

c. Marking requirements - indicating element not permanently attached or 

covered on separate CC (in addition to marking for all device).........................

Accuracy class................................................................................................

Nominal capacity............................................................................................

Value of scale division with nominal capacity, if not apparent......................

Scales designed for special purposes..............................................................

Maximum number of scale divisions (nmax)....................................................

d. Marking requirements for weighing and load-receiving element not 

permanently attached or covered on separate CC (in addition to marking 

for all devices). ..................................................................................................

Accuracy class................................................................................................

Nominal capacity............................................................................................

Scales designed for special application. .........................................................

Maximum number of scale divisions (nmax). ..................................................

Minimum verification scale division for which device complies with the 

requirements (emin or d). .................................................................................

S.6.3.

(1/1/86)

Retroactive

(1/1/83)

(1/1/86)

(1/1/88)

S.6.3.

(1/1/86)

Retroactive

(1/1/86)

(1/1/88)

(1/1/88)

4. Installation...................................................................................................................... UR.2.3., UR.2.4.,

G-UR.2.

5. Design of balance, tare, level, damping, and arresting mechanisms. ............................. S.2.1., S.2.3., S.2.5.1.

6. Design of weighing elements. ........................................................................................ S.4.
NIST Handbook 112 (2015)

EPO – No. 9, Part 2 – Monorail Scales and Meat Beams – Mechanical

Monorail Scales (Rev 09/14) DRAFT Page 13 of 16

H-44 General Code 

and Scale Code 

References

Inspection (cont.):

7. Maintenance, use, and environmental factors (cleanliness, obstructions, 

modifications, etc.). ....................................................................................................... G-S.2., G-UR.1.2., 

G-UR.3.1., G-UR.4., 

UR.4.3.

SAFETY REMINDER!!!

− Check the inspection site carefully for safety hazards and take appropriate precautions.

− Use caution in moving in wet, slippery areas.

− Use personal protection equipment appropriate for the inspection site.

− Be sure that a first aid kit is available and that the kit is appropriate for the type of 

inspection activity.

− Check to be sure the scale supports are adequate to support the scale, test weights equal to 

the capacity of the scale, and test platforms or chains used to suspend test weights.

8. Assistance........................................................................................................................ G-UR.4.4.

9. Provisions for testing and accessibility............................................................................ UR.2.9., G-UR.2.3.

Pretest Determinations:

1. Tolerances.

Acceptance/Maintenance.................................................................................................

Application.................................................................................................................

Tolerance values:

Scales marked with an accuracy class. ...................................................................

Scales not marked...................................................................................................

Discrimination. ................................................................................................................

G-T.1., G-T.2.

T.N.2.1., T.N.2.3., 

T.N.2.4.

T.N.3.1., T.N.3.2.,

Table 6 (Class III),

T.N.4., T.N.5.

T.1.1., T.N.3.1., 

Table 6 (Class III), 

T.N.3.2. T.N.4.1., 

T.N.4.2., T.N.5.

T.N.7.1.*
NIST Handbook 112 (2015)

EPO – No. 9, Part 2 – Monorail Scales and Meat Beams – Mechanical

Page 14 of 16 Monorail Scales (Rev 09/14) DRAFT

H-44 General Code 

and Scale Code 

References

Pretest Determinations (cont.):

2. Select trolleys, trees, chains, or other auxiliary gear necessary to suspend test 

weights on rail or meat hook. If two or more trolley-and-tree combinations are used; 

they should be uniform in weight ± 52 grams (± 2 ounces).

SAFETY REMINDER!!!

− Wear appropriate personal protection equipment such as hard hats and eye protection to prevent 

injury from overhead meat hooks, hanging carcasses, falling weights, and slipping on slick 

surfaces.

− Wear safety shoes to prevent possible injury from falling weights and slipping on slick surfaces.

3. Minimum test weights and test loads. ............................................................................. N.3.

Test Notes:

1. Suspend auxiliary gear (trolleys, trees, chains) from live rail.

2. If beam scale, place small error weights on or suspend from the live rail or hook. 

The value of the smallest weight should be equal to the minimum tolerance value 

and the total of all the weights should be equal to the tolerance at maximum test 

load.

3. Balance in auxiliary gear and test weights.

4. Check repeatability and agreement between indications and between indications and 

recorded representations throughout test. ...................................................................... T.N.4.1., T.N.5., 

G-S.5.2.2.(a)

5. Check zero-load balance each time test load is removed. ............................................. N.1.9., G-UR.4.2

6. If scale is equipped with a type-recording beam or printer, print a ticket at each test 

load................................................................................................................................ G S.5.6., 

UR.1.3.(1/1/86)

Static Test:

SAFETY REMINDER!!!

− Wear safety shoes!

− Use proper lifting techniques!
NIST Handbook 112 (2015)

EPO – No. 9, Part 2 – Monorail Scales and Meat Beams – Mechanical

Monorail Scales (Rev 09/14) DRAFT Page 15 of 16

H-44 General Code 

and Scale Code 

References

Static Test (cont.):

1. Sensitivity teat at zero[load (weighbeams only)..............................................................

Discrimination test at zero only (dial indicators only).....................................................

N.1.4.

N.1.5.

2. Increasing load test........................................................................................................

a. Beam scales. Test at not less than three points or notches on weigh-beam.

Scales not equipped with a full capacity beam should be ratio tested using 

standard weights on counterpoise hanger. 

When ratio testing, test poise and beam by substituting poise position with the 

removal of standard weights from counterpoise hanger.........................................

N.1.1.

N.1.7.

b. Dial scales. Test at not less than three points on reading face, including all 

possible quarters of capacity. Test all unit weights possible. If equipped with 

tare bars, test at one half and full capacity of each bar.

3. Shift test. Use test load equal to the largest load that can be anticipated to be 

weighed at the installation, but never less than one-half capacity. Apply load 

successively on the right end, the left end, and the center of the live rail. This can be 

conducted during the increasing load test........................................................................ N.1.3.5.

4. Beams and balance indicators only, test for SR at the maximum test load. ....................

Dials only. Conduct the discrimination test at maximum test load. ...............................

N.1.4.

N.1.5.

5. Dials only. Conduct the decreasing-load test at one-half of the maximum test load 

(at no less than one-half of the dial face capacity............................................................ *N.1.2.1., N.1.2.2.

6. Beams only. Conduct a counterpoise weight accuracy test (see HB 44 Section 2.23. 

Weights paragraph T.1. and appropriate Table 1. Maintenance Tolerance for 

Avoirdupois Weights or Table 1. Maintenance Tolerance for Metric Weights). ......... HB 44 Section 2.23 

paragraph T.1.

7. Remove all test weights and determine any zero-balance change. ................................ N.1.9., G-UR.4.2.
NIST Handbook 112 (2015)

EPO – No. 9, Part 2 – Monorail Scales and Meat Beams – Mechanical

Page 16 of 16 Monorail Scales (Rev 09/14) DRAFT

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