Development of Chemical Precipitation Purchased 

Equipment Costs:

Chemical Feed Systems

Purchased Equipment Costs are the sum of the following cost elements:

(1) Pump Costs

(2) Tank Costs

(3) Chemical Feed System Costs

(4) Mixer Costs

(5) Clarifier Costs

(6) Filter Press Costs

(7) Sand Filter Costs

Each cost component includes the cost of freight and associated ancillary equipment such as piping, 

valves, and controllers.

The following documents provided by a vendor support EPA’s development of cost element (3) by 

providing details and specifications for solid chemical feed systems used in the Steam Electric cost 

model.
© EnPro Technologies Ltd Revision: 1/2011 

SILO PACTM 

Reduce Operator Handling of Dry Chemicals 

Typical Hydrated 

Lime Silo 

Configuration 

 The Most Efficient Delivery Method in the 

Industry 

 Various Pump Types, and Models 

Available 

 8’ to 15’ Diameter Available in Factory 

Welded 

 16’ to 36’ Diameter Available in Field 

Welded 

 Concave Mix Tank for Maximum 

Equipment Room Space 

 All Piping and Conduit located under floor 

or above head to eliminate hazards 

 PLC Controlled Systems for Complex 

Processes 

The EnPro Silo Pac is a unique product that 

eliminates quality control issues that are typically 

seen in most silo systems. EnPro provides the 

Silo Pac in two sections as described below. 

The lower equipment room is where all of the 

process equipment is located this section is 

typically 12’ diameter by 11’ tall. This section will 

have all of the process equipment installed at our 

manufacturing facility. Here we can not only 

install the equipment, but we also operate the 

entire system as if it was already in the field. This 

insures that startup will be as painless for the 

customer as possible. 

The upper storage section will be shipped to the 

job site so the contractor can bolt it to the top of 

the lower equipment room. Each section has a 

junction box located at the bolting flange to allow 

the contractor to electrically connect the two 

pieces. This process is the most efficient delivery 

method in the industry. 

Custom models and options 

available, consult factory. 

Contact us at 

4225 NE Port Dr. 

Lee’s Summit, MO 64064 

816-795-6333 phone 

816-795-6030 fax 

www.enpro-tech.com 
© EnPro Technologies Ltd Revision: 1/2011 

The EnPro Silo Pac is used to store, feed, dissolve, and deliver 

chemical to the desired process point. They are used in many 

applications for municipal and industrial waste and water 

treatment applications. Typical applications include: 

 Neutralization and PH control 

 Heavy metal removal 

 Taste/odor control 

Each silo is custom engineered to your specifications with 

multiple options available. These systems normally include: 

 Storage Silo (pre assembled two piece design) – 

Sizes range from 8’-0” up to 15’-0” in diameter. 

 Pneumatic silo fill pipe assembly with NEMA 4X 

operator station. 

 Dust collection system (mounted on roof). 

 Osha approved caged ladder & hand rail for roof 

access. 

 Silo level devices. Continuous and or point level. 

 Bin Activator or Vibrators. 

 Volumetric screw feeder with washdown inverter duty 

motor and variable frequency drive. 

 Slurry make down/storage tank with mixer, and level 

devices. 

 Slurry feed pumps if required. 

 All required piping and valves. 

 Local control system with programmable logic 

controller (PLC) including pre-programmed system 

logic. All systems are completely tested with water for 

the engineer or customers viewing before leaving our 

facility. All of EnPro’s control panels are UL or CUL 

listed. 

 Silo systems are provided with ventilation fans, 

heaters and lighting. The interior of the skirt section is 

insulated. 

The Silo Pac Advantages

 Factory testing on all of our systems. These tests 

include:

o Pressure testing all piping, and valves.

o Hydrostatic testing of our mix tanks.

o Complete sequencing of all devices, 

including motors and solenoids.

o All inspected by an EnPro quality assurance 

inspector.

 Due to the fact that EnPro provides the most 

complete pre assembled silo system on the market, it 

ultimately saves time for the contractor, and 

eliminates frustrating installation issues.

 EnPro’s service and technical support staff are the 

most experienced in the industry. 

Contact our applications department for more 

details on the Silo PAC System at the following: 

David Jones: (816) 350-5242 

Troy Litherland: (816) 350-5223 

Jesse Kuntz: (816) 350-5244 

SILO PACTM 

Reduce Operator Handling of Dry Chemicals 
[project] Page 1 of 11

PLEASE CONTACT ENPRO FRO SPECIFICATIONS IN WORD FORMAT

SPECIFICATION: BULK DRY CHEMICAL SILO STORAGE AND FEED SYSTEM-MIX TANK

ENPRO TECHNOLOGIES LTD.

NOTE: All items in red are optional or decisions to be made 

regarding voltage, tank capacity, metering pumps if applicable, 

panel enclosure material, etc.

PART 1 GENERAL

1.01 SECTION INCLUDES

A. Bulk dry chemical silo storage and feed system

1. The bulk dry chemical silo storage and feed system shall be capable of 

storing up to XXX cubic feet of dry chemical, metering the dry chemical and 

mixing the chemical with water for feed to process. 

1.02 WARRANTY

A. The system shall be covered by a one (1) year limited warranty against defects 

in materials and workmanship. 

1.03 SUBMITTALS

 A. Product Data:

1. One (1) electronic copy of submittal data will be supplied for the system.

2. One (1) Hard copy and one (1) electronic copy of the operations and 

 maintenance manual will be shipped with the system.

 B. Shop Drawings:

 1. Component data and shop drawings of the system will be supplied, including 

 dimensions, weight, and parts list.

 2. Control panel elevation, control schematics and component data will be

 supplied.

1.04 QUALITY ASSURANCE

 A. Manufacturers Qualifications:

1. The equipment shall be the product of a systems supplier who is regularly 

engaged in chemical feed system design and supply.

2. The major components of the Bulk Storage and Feed System shall be 

furnished by a single supplier to facilitate maintenance and stocking of repair 

parts as well as providing a single source of responsibility over the system.
[project] Page 2 of 11

3. The specifications and drawings covered by this section are based on the 

equipment manufactured by EnPro Technologies Ltd.

4. The system supplier shall prepare shop drawings that verify that each system 

component is compatible with other components of the system, and that 

piping materials and sizes are appropriate, and that all devices necessary for 

a properly functioning system have been provided.

5. Demonstrate to the satisfaction of the ENGINEER that the quality is equal to

 equipment made by the manufacturers named herein.

6. Owner may require verification of qualifications by requesting the following 

information:

a) Financial Capability.

b) That the manufacturer maintains a design office with a qualified technical 

staff.

c) That the manufacturer has and will maintain competent service personnel 

to service equipment furnished.

d) That manufacturer has successfully provided similar work for at least five 

(5) years.

 B. System to be pre-assembled and shop-tested to the fullest extent practical to 

 assure compliance with the operational requirements.

PART 2 PRODUCTS

2.01 MANUFACTURERS

 A. Provide a quantity of _____ bulk dry chemical silo storage and feed system(s) as 

 manufactured by EnPro Technologies of Lee’s Summit, MO or engineer preapproved equal. Should equipment of a different type or size which otherwise

differs from that specified herein be offered, such equipment shall be acceptable 

only on the basis that any revisions in the design and/or construction of the 

structure, piping, appurtenant equipment, electrical work, etc, required to 

accommodate such a substitution shall be made at no additional cost to the 

Owner, shall be the responsibility of the Contractor and shall be as approved by 

the Engineer.

2.02 IDENTIFICATION

 A. A corrosion resistant nameplate shall be supplied on the system. Nameplate 

 information to include equipment model number, serial number and contact 

 phone number for support.

2.03 EQUIPMENT

A. Storage Silo:

1. The storage silo shall be of all welded, mild steel construction. Silo roof,

straight-wall, cone, and support skirt shall be fabricated of ASTM A-36 steel 

per manufacturer’s professional engineer’s design based on the silo 

diameter, height & configuration. The maximum overall silo height shall be 

approximately 33 feet (not including bin vent filter / dust collector), and 12 feet 
[project] Page 3 of 11

diameter. The height of the silo shall be such that the usable capacity of the 

storage section is approximately 1500 cubic feet.

2. The storage silo shall be designed to accommodate all dead loads including 

vibration from bin vibration devices plus a full live load of chemical (XXXXX 

lbs minimum for design purposes) having a bulk density of XX pounds per 

cubic foot (for weight calculation purposes). Seismic load forces shall be per 

IBC 2006.

3. The interior of the storage compartment shall be smooth with no inward 

projecting elements (except for plates to protect the bin level sensors 

specified elsewhere).

4. The storage bin shall be completely dust-tight and watertight. All connections 

to the storage compartments shall be by flanged gasketed connections. 

Gaskets shall be of the full-faced type of neoprene or approved equal. All 

bolted connections shall utilize zinc plated or stainless steel nuts, bolts, and 

washers.

5. The interior skirted portion of the silo shall be furnished with minimum 1” 

thick, closed-cell foam. All seams are to be taped.

6. The storage silo shall be delivered to the job site in two sections as outlined 

below.

a. The equipment room section shall house all equipment including but 

not limited to mix tank, feeder, bin activator, pumps, and control panel. 

All of which shall be installed at the factory and pre-piped and prewired and hydraulically tested and demonstrated to the customer at 

the manufacturers facility. The equipment room section shall consist 

of the lower silo ring and shall be supplied with a bolting flange to 

allow the storage section to bolt to the top of the equipment room 

section.

b. The storage section shall be structurally designed to store the 

required chemical. The storage section shall have all components 

including but not limited to level devices, dust collector blower, and 

dust collector shaker. All of which shall be pre-wire to junction boxes.

7. Anchor bolts, Sixteen (16), to be supplied by the installing contractor.

B. Painting and Preparation:

1. Sandblast to SSPC-SP-6.

2. Primer shall be a corrosion inhibitive polyamide epoxy primer.

3. Finish Coat shall be a two-component polyurethane. Factory-applied, 

thermally cured.

4. The color shall be EnPro standard.

 

 C. Bin Roof:

1. The bin roof shall be pitched 1:12 for drainage purposes. The roof shall be 

designed to support all roof appurtenances, plus superimposed live load of at 

least 50 pounds per square foot. 

2. At least four (4) lifting lugs shall be provided at the top of the bin. Lifting lugs 

shall be 3⁄4-inch thick or larger steel plate with 2-inch diameter hole for use 

with lifting devices.

3. Railings and kick plates shall be provided around the perimeter of the storage 

bin roof as shown on the drawings. All ladders, cages, platforms, and 
[project] Page 4 of 11

handrails shall conform to OSHA standards as well as any other applicable 

building or safety codes. All handrails shall be 2-rail handrail type with kick 

plate.

4. The bin roof shall have the following connections:

a. A flanged nozzle type connection of 1⁄4-inch steel plate suitable to support 

the bin vent filter.

b. A 24-inch diameter (minimum) steel man way with hinged, gasketed 

cover and handle-type locking mechanism.

c. A flanged nozzle suitable for use with the high level sensor.

d. A flanged nozzle suitable for use with a pressure vacuum relief valve.

e. A flanged nozzle suitable for use with the target box of the chemical 

supply piping.

 D. Discharge Hopper:

1. The discharge hopper shall be cone shaped with side slope measuring 60 

degrees from horizontal. The bottom of the hopper shall have a flanged 

connection and drilled to match the equipment specified herein.

2. The side of the storage compartment shall include an opening for the 

intermediate and low level sensors and located to be accessible to the 

operators. Pitched plates with angles greater than the angle of repose of the 

chemical being stored shall be positioned above the level sensor to protect 

the sensor from falling material during silo filling. These plates shall be the 

only protrusion on the inside silo wall.

3. Size of anchoring pressure plates shall be determined by manufacturer’s 

design as designed by a professional engineer.

 E. Wall Penetrations:

1. All wall penetrations shall have a minimum thickness of 1/’4-inch for all 

square or rectangular shapes, all round penetrations shall not be less than 

schedule 40. All penetrations shall be completely seal welded.

 F. Flanges:

1. Where applicable, all flanges shall be a minimum 150-pound connection 

unless otherwise noted within these specifications.

2. Angle Rings shall be provided at the cone intersect and silo roof intersect if 

required by manufacturers manufacturing process. Angle rings shall be 3” x 

3” x 1⁄4” rolled angle. If required for structural purposes, suitable flat plat is 

acceptable.

 G. Bin Level Switches: 

1. Bin level switches shall be mounted for high, intermediate, and low level 

indication in the chemical storage bin. These switches shall be of the 

stainless steel rotating paddle type, electrically operated. All bin level 

switches shall be easily accessible. An audible and visual alarm shall be 

activated when either high or low-level bin switch is activated. High and low 

level switches shall include an extra set of contacts for user direct hookup on 
[project] Page 5 of 11

terminal strips provided in the main control panel for remote monitoring 

purposes.

2. The bin level switches shall be manufactured by Bindicator or engineer 

approved equal. 

 H. Bin Activator(s): 

1. A heavy-duty, motor driven bin activator shall be mounted to the silo 

cone. The bin activator shall be a minimum of 4-foot diameter with a 

discharge opening suitably sized for the mating equipment. Controls of 

the bin activator will be inter-locked with the feeder control circuit and will 

operate only when the feeder is in operation.

2. The bin activator shall operate on 460 volt, three-phase power.

3. The bin activator shall be as manufactured by Kinergy or engineer 

approved equal.

 I. Maintenance / Knife Gate: 

1. A manually operated, slide type maintenance gate shall be provided 

between the cone and flexible connection.

2. The bin gate shall be manually operated, dust tight and arranged for easy 

access by plant operators. 

3. The bin gate shall be manually operated with a chain wheel arrangement 

for ease of operation from the equipment room floor.

4. The bin gate shall have a minimum clear opening of 144 square inches to 

provide chemical flow out of the storage bin. 

5. The bin gate shall be as manufactured by Dezurik or engineer approved 

equal.

 J. Bin Vent Filter: 

1. A bin vent filter shall be flange mounted on the chemical storage bin roof. 

The unit shall be pre-wired and functionally checked. Units shall be 

mounted by the installation contractor. Unit shall be an open bottom, 

flanged mounted mechanical shaker type collector designed to shake 

retained bag dust directly into the storage silo during shaker operation.

2. The bin vent filter shall have a venting capacity of 1500 cfm, based upon 

a maximum air to cloth ration of 5 cfm per square foot, at 3” of water 

differential.

3. Filter shall be fabricated of weatherproof and drip-proof construction, with 

self-contained bag shaker and exhaust fan assemblies.

4. All parts of unit subject to service or maintenance, shall not be more than 

five feet above the mounting flange, and be accessible without the use of 

any service platforms or ladders.

5. The bin vent filter housing shall be fabricated of not less than 12 gauge 

carbon steel. The housing shall be of one-piece construction with all 

seams continuously welded. Spot welding or skip welding shall not be 

acceptable. The housing shall have two (2) access doors, which shall be 

totally removable, or be able to open on a swing hinge assembly for quick 

inspection. The doors shall give complete access to the filter bag 

compartment and to the shaker compartment.

6. The cloth area of the filter shall be 300 square feet.
[project] Page 6 of 11

7. Filter bags shall be cylindrical and removable without the use of any 

tooling. Each bag shall pivot on a filter tube sheet and hang from the 

shaker mechanism with an automatic self-tensioning spring. Envelope 

type bags or bags without self-tensioning shall not be acceptable.

8. Unit shall be designed so that an operator may be able to open the 

inspection door during operation, without allowing dust to escape while 

unit is in operation. Each bag shall be constructed of materials suitable 

for handling the chemical specified. All bags shall be installed at the 

factory, Bag manifold shall be constructed to prevent filter bags from 

falling into the storage silo.

9. An electrically operated mechanical bag shaking mechanism shall be 

provided as an integral part of the bin vent filter. Shaker assembly shall 

be operated by a 1/3 HP, 230/460, 1725 RPM, TEFC motor.

10. Unit shall contain a mechanical oscillator assembly, sealed for life 

lubrication system, and be enclosed in a weatherproof enclosure.

11. Oscillator assembly shall be directly connected to a free-floating bag 

holding manifold which shall shake the dust collector bags during 

operation. Shaking mechanism shall be a direct drive unit. Belt drive 

units are unacceptable.

12. An exhaust fan shall be included as an integral part of the bin vent 

assembly. The fan shall be a squirrel cage type, operating at 3450 RPM. 

The unit shall provide a negative pressure within the storage silo during 

truck unloading operation, and shall be operated by a 3 HP, 230/460 

VAC, TEFC motor.

13. NEMA 3R disconnect switches shall be furnished for the exhaust fan and 

shaker mechanism motors. Disconnects shall be factory mounted and 

wired adjacent to each motor.

14. The unit shall be Model 17-04, as manufactured by EnPro Technologies 

without exception. 

 K. Silo Fill Piping: 

1. Conveying Pipe: A 4-inch diameter, Schedule 40, carbon steel conveying 

pipe shall be furnished complete with all the necessary compression type 

couplings. Conveying pipe shall begin at the truck unloading station and 

terminate at the inlet target box. Fill system conveying pipe shall be 

mounted at the factory, and removed for shipping purposes. The 

CONTRACTOR shall be responsible for re-mounting the conveying pipe 

in the field.

2. Long Radius Elbows: Wherever the filling pipe makes a turn, a 4-inch 

diameter Schedule 40, carbon steel elbow, 4 ft. radius (minimum), shall 

be provided and installed. Compression type couplings shall be provided 

to join the elbows with the vertical fill lines, the inlet target box, and the 

individual horizontal/vertical runs.

3. Fill System Pipe Adapter: A 4-inch bronze Kamlock type adapter shall be 

mounted on the fill pipe at the truck unloading station. A bronze or 

painted carbon steel dust cap and chain shall be provided.

4. Inlet Target Box: A heavy-duty inlet target box shall be mounted on the 

storage bin roof flanged connection. Target box shall be designed to kill 

the velocity of the chemical being conveyed, and allow it to drop into the 
[project] Page 7 of 11

storage bin in an even patter. Target box shall be provided with a 

removable end cap to facilitate cleaning of the fill system.

 L. Limit Switch: 

1. A limit switch shall be mounted on the pipe adapter to provide automatic 

operation of the bin vent filter, during and after truck unloading cycle. 

Limit switch assembly shall be adjustable and secured to a heavy-duty 

mounting bracket for dependable operation. Limit switch shall be 

complete with two sets of N.O. and two sets of N.C. contacts wired into 

the unloading control panel to numbered terminal strips for remote 

indication.

 M. Truck Unloading Control Panel:

1. A NEMA 4X stainless steel control panel shall be wall mounted at the 

termination of the fill pipe and as shown on the drawings. Panel shall be 

pre-wired by the supplier and contain, but not be limited to the following 

items of equipment: High, reorder and low bin level indicating lights, 

alarm horn with press-to-test pushbuttons, H-O-A switches for bin vent 

filter motor(s), and adjustable timer, (0-15 minutes) for operating bin vent 

filter mechanical bag shaker. Numbered terminal strips pre-wired for 

connection of bin level alarms and unloading indication and a numbered 

terminal strip with at least 25 percent extra terminal blocks shall be 

provided. Truck unloading station shall be installed and tested at the 

factory. Truck unloading panel shall be integrated into the silo PLC. All 

wires shall be numbered with adhesive labels. All electrical components 

interconnected to the control panel shall terminate at numbered and 

labeled terminal blocks. The terminal blocks shall be sized for 14 ga. wire. 

Wires shall be neatly run through wire race-way and numbered with 

adhesive type labels. The truck unloading panel shall be manufactured by 

a UL508 panel shop. All control panels shall be UL508 certified and 

labeled. Control panels that do not have a UL label shall not be 

acceptable.

 N. Volumetric Feeder:

1. A heavy-duty volumetric feeder shall be provided to feed chemical at a 

maximum rate of XX.X pounds per hour.

2. Feeder controls shall incorporate an ac drive, which shall be capable of 

receiving a 4-20mA signal from the silo PLC located in the system control 

panel. The drive must be capable of sending a 4-20mA signal to the silo 

PLC. The signal shall be proportional to the actual drive speed. This 

speed shall be displayed on the silo operator interface terminal. The 

drive shall be a Power Flex 40 manufactured by Allen Bradley or engineer 

approved equal.

3. Feeder shall have a repeatable accuracy of plus or minus 2 percent.

4. Feeder shall have an inlet opening of at least 144 square inches to insure 

a positive flow of chemical out of the storage hopper through the feeder.

5. Motor shall be a TENV 1/2 HP (minimum) inverter duty permanent 

magnetic type.

6. Materials of Construction:

i. Housing Assembly – 304 stainless steel, minimum 10 gauge.

ii. Discharge Spout – 304 stainless steel and PVC
[project] Page 8 of 11

iii. Auger – 304 stainless steel.

7. Mechanical Features:

i. Solid flight feed auger

ii. The feeder discharge shall include a PVC downspout with 

removable cap.

iii. The inlet of the downspout shall be slotted for easy removal. 

iv. The downspout shall have a close tolerance fit to the adapter 

plate on the mix tank.

 O. Transitions:

1. Provide a flexible transition required to interconnect volumetric feeder to 

silo discharge while reducing vibration transfer from the bin activator to 

the process equipment.

2. Provide rigid transitions as required to interconnect volumetric feeder to 

the flexible transition at the silo discharge.

 P. Solution/Mix Tank:

1. A XXX-gallon chemical solution/slurry mix tank shall be provided below 

the chemical feeder.

2. The mix tank shall be constructed of 10-gauge type 304 stainless steel.

3. The tank shall include a minimum of four (4) hold down clips for anchoring

4. The tank design shall provide for a minimum of 4” freeboard, be properly 

baffled to prevent short-circuiting of chemical from tank inlet to outlet, and 

will include a hydraulically operated dust and vapor remover system. The 

water from the dust and vapor remover shall be directed into the opposite 

side as the feeder inlet side of the baffle.

5. The solution tank shall have, as a minimum, the following connection:

i. Inlet water connection – 1 1⁄2”.

ii. Tank drain connection – 2”.

iii. Overflow connection – 2”.

iv. All solution/slurry tank piping shall be rigidly mounted on the 

tank at the factory.

6. The solution tank shall have easy access to internal operating devices for 

observing operation and performing routine maintenance. Each solution 

tank shall have a stainless steel hinged or lift-off cover to observe 

operation and provide access to all system components within the tank.

7. A mechanical mixer shall be provided to maintain a uniform strength 

solution or slurry. The mixer shaft and mixer blades shall be type 304 

stainless steel. The mixer motor shall be a minimum 1⁄4 HP, TEFC, 480 

VAC, 3 Ph, 60 Hz, inverter duty. The mixer shall be controlled by a 

variable frequency drive to allow turn down. The drive shall be a Power 

flex 4 manufactured by Allen Bradley or engineer approved equal.

8. A dilution water panel for control of supply water to the solution tank shall 

be furnished. It shall contain Schedule 80 PVC piping. The water supply 

lines and distribution of inlet water shall have the following components 

as a minimum:

i. Qty 1 - 1 1⁄2” solenoid valve.

ii. Qty 1 – Pressure gauge with scale of 0 to 100 psi.

iii. Qty 1 – Rotometer with 0 to XX GPM.

iv. Isolation Valves as required.
[project] Page 9 of 11

9. The solution tank shall be provided with an automatic level alarm system 

of the pressure transducer type for monitoring level continuously. The 

pressure transducer shall be compatible with the required chemical. The 

pressure transducer shall send a 4-20mA signal to the silo PLC to set the 

proper alarms. The pressure transducer shall be manufactured by 

Endress & Hauser or engineer approved equal. The level points shall be 

as follows:

i. High Level Alarm: This alarm function shall light a light on the 

control panel, sound an audible alarm on the control panel, 

close a dry contact for remote alarm indication, and shut off 

the dry chemical feeder.

ii. System Disable: This level point will turn off the feeder and 

solenoid valve.

iii. System Enable: This level point will turn on the feeder and 

solenoid valve.

iv. Low Level Alarm: This alarm function shall light a light on the 

control panel, sound an audible alarm on the control panel, 

close a dry contact for remote alarm indication, shut off the dry 

chemical feeder, and close the control valve.

 Q. Slurry Pumps:

1. The pumps shall be manufactured by XXXXXX or engineered preapproved equal.

2. The pump capacity shall be XX gpm at XXpsi.

3. The lime system shall be supplied with two XXXXX pumps located inside 

the equipment room of the silo.

4. The pumps shall be variable speed and controlled by a variable frequency 

drive. The drives shall be provided by the silo manufacturer and located in 

the lime main control panel. The variable frequency drive shall be Allen 

Bradley power flex 40 or engineer pre-approved equal.

 R. Controls:

1. Provide a wall mountable NEMA 4X, 304 or 316 stainless steel system 

control panel to control the operation of the chemical mix tank and its 

associated equipment. The main control panel shall house all electrical 

components required for a fully functional system. The system shall be 

designed to receive a 480 VAC / 3 phase service. The control panel shall 

supply all required transformers, relays, and other control devices 

required for a complete operable system. The control panel and all 

components shall be industrial duty. All electrical components 

interconnected to the control panel shall terminate at numbered and

labeled terminal blocks. The terminal blocks shall be sized for 14 ga. wire. 

Wires shall be neatly run through wire race-way and numbered with 

adhesive type labels. 

2. The system shall utilize a programmable logic controller. The PLC shall 

be capable of communicating with the supervisory system via Ethernet. 

The PLC shall be manufactured by Allen Bradley or engineer approved 

equal.

3. The operator interface terminal shall be located on the front of the 

enclosure. The operator interface shall have all required software 

pushbuttons and selector switches for a fully functional system. The 
[project] Page 10 of 11

operator interface shall display all running indications, all alarm 

messages. The operator interface shall be a Panel View Plus 

manufactured by Allen Bradley or engineer approved equal.

4. The main control panel shall be manufactured by a UL508 panel shop. All 

control panels shall be UL508 certified and labeled. Control panels that 

do not have a UL label shall not be acceptable. 

5. The operator interface terminal shall have the following features:

a. Auto Control Page

I. System Start

II. System Stop

III. Concentration Numeric input (0-10%)

IV. Master Auto

V. Master Hand

VI. Running indications for the following:

1. Feeder

2. Mixer

3. Solenoid Valve

4. Bin Activator

5. Exhaust Fan

6. Pump 1 

7. Pump 2

8. Actual Speed Readout for the following:

a. Feeder (0-100%)

b. Pumps Page

I. Pump 1 On/Off/Remote

II. Pump 2 On/Off/Remote

III. Pump 1 local speed set point (0-max gpm)

IV. Pump 2 local speed set point (0-max gpm)

V. Pump 1 Actual speed (0-max gpm)

VI. Pump 2 Actual speed (0-max gpm)

c. Alarms Page

I. Alarm messages for the following alarms:

1. Mixer Overload

2. Feeder Fault

3. Pump 1 VFD Fault

4. Pump 2 VFD Fault

5. Pump 1 Leak Detected

6. Pump 2 Leak Detected

7. Bin Activator Overload

8. Mix Tank Low Level

9. Mix Tank High Level

d. Mix Tank Page

I. Mix Tank Level (0-100%)

II. High Level Set Point Numeric Input

III. Low Level Set Point Numeric Input

 

2.06 OPTIONS

1. Water Pressure reducing valve (provided loose for field installation).
[project] Page 11 of 11

2. Load cells for bulk bag frame weight

3. Loss of weight volumetric feeder.

4. Electronic water flowmeter with analog output to volumetric feeder for 

constant concentration of chemical. Requires PLC based controls.

PART 3 EXECUTION

3.02 INSTALLATION

1. Bulk dry chemical silo storage and feed system(s) shall be installed in strict 

 conformance with the manufacturers installation instructions. Installation to 

 include sub-asembly of major components, field piping, interconnecting wiring 

 and all supports and miscellaneous hardware not specifically stated herein. This 

 work shall include bringing sources of power, water and compressed air (if 

 required) to the system suppliers termination points. 

2. Checkout of final installation, start-up, calibration and instruction of operating 

personnel shall be performed by an authorized representative of the 

manufacturer. Startup service to be performed in two (2) trips; (1) trip of three 

(3) days for installation check and equipment start-up and (1) trip of two (2) days

of on-site training of personnel exclusive of travel.

.

- END SECTION-
[Schematic diagram has been redacted to prevent disclosure of material for which a claim of confidential

business information has been made.]
[Schematic diagram has been redacted to prevent disclosure of material for which a claim of confidential

business information has been made.]