EMRT1Square root calculator
List ofproducts

WO81

EMRT1RoHS

Square root calculator
This instrument performs square root calculation ofWO71

FR51A

MS99

an electric signal that is in proportion to the input
pressure
and outputs a current signal that is in proportion to theairflow rate.
The input signal and the output signal are electricallyinsulated from each other.

MS99S

MS61A-RA

QDP33

EMD8A

EMD7

EMT1

EMTGP1

EMRT1

EMT1H

EMT6

EMP5A

EMRT1

HWS15A

Accessories
Application

Precautions
Maintenance

Product code

EMRT1 A11Output signal
Input signal
Power source1

4–20 mA DC

1

4–20 mA DC

A

100 V AC, 50/60 Hz◆When making an inquiry or placing an order, specify the above product code.
◆When you use this product for airflow rate/airflow speed measurements incombination with an adjustment meter, we need to obtain the specifications of
the pressure detection side. Fill out the airflow rate/airflow speed specification
document preparation sheet on page 15, and inform us of the data.

97

EMRT1

Square root calculator
EMRT1

List ofproducts

Square root calculation input/output comparison tableSpecifications
EMRT1

Model
Input signal
Output signal
Square root output
cut point
Accuracy

Output value±1% FS (at 20°C)
However, at output signal range of 15 to 100% FS±0.01% FS/°C (at 0°C to 40°C)

Table for output signal

100 V AC ± 10%, 50/60 Hz, approx. 3.5 VA
Polycarbonate and ABS resin
0 to 50°C (no freezing allowed)

Input signal
4–20 mA DC

Between terminal and case: 20 MΩ or higher (500 V DC megger)
Between power terminal and case: 1000 V AC, 50/60 Hz, for one minuteRail mounting (applicable rail: 35 mm wide DIN rail)
Approx. 300 g

Output signal
4–20 mA DC

4 mA

Zero point

4.0 mA

8 mA

1/2 span point12.0 mA

20 mA

Span point

20.0 mA

90% RH or below (no condensation allowed)◆For use environment, refer to page 118.

Square root output cut point
This refers to the point where output is cut so as not to perform square root output of
the output signal in the range of 0% to 15% of FS. The results of comparison of input
signals and output signals are shown in the table on the right. Since the input value
becomes extremely small as the output value decreases, and then enters an action
range out of the scope of the accuracy of the calculator, the cut point is set. In thisinstrument, the value range of 15% FS and below, which does not affect the actual use,
is cut off.

↑50
150

WO71

FR51A

MS99

MS99S

MS61A-RA100（％FS）

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Temperature
characteristics
Power voltage
Exterior material
Operating ambient
temperature
Operating ambient
humidity
Insulation resistanceWithstand voltage
Mounting method
Mass（0．5）2 ×100％＝25％（0．2）2 ×100％＝4％（0．15）2×100％＝2．25％（0．1）2 ×100％＝1％（0．05）2×100％＝0．25％

50％20％
15％10％5％

4 to 20 mA DC (input resistance of 50 Ω)
4 to 20 mA DC (load resistance of 500 Ω or lower)
15% FS or below

WO81

Input value

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025100（％FS）（x ％FS）→,QSXWVLJQDO&DOFXODWLRQIRUPXOD \（％)6）＝[（％)6）î

External dimension drawing

QDP33

EMD8A

EMD7

EMT1$WWDFKPHQWRIQDPHSODWH',1UDLO PP0WHUPLQDOVFUHZ

EMTGP12INPUT

345OUTPUT

6S.G.

35ZEROSPAN
100VAC
78E

91011EMT1H

73112EMT611255

EMP5A！
CautionTerminal screw tightening torque: 0.7 to 1.0 N·m
Do not tighten to a torque that exceeds the specified value because
doing so breaks the instrument body.

Electronic circuit block diagram

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Accessories
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Precautions
Maintenance

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98

Warranty■Warranty period
The warranty period for our product is one (1) year from delivery to the location specified by the orderer who makes a direct transaction
with us.

■Scope of warranty
If any failure or defect attributable to us becomes clear during the above warranty period, we will repair the product or supply asubstitute product free of charge. However, even during the warranty period, we will exclude the product from the scope of the warranty
if the failure or defect corresponds to any of the following:(1) The failure or defect was caused by an unreasonable condition, environment, handling, or usage not mentioned in theinstruction manual, specifications, and our product catalog.
(2) The failure or defect was caused by a factor other than our product.
(3) The failure or defect was caused by a modification or repair conducted by a party other than us.
(4) The failure or defect was caused by an event that could not be foreseen at the scientific and technical levels at the time ofproduct shipment from us.
(5) The failure or defect was caused by an external factor not attributable to us, such as acts of God and disasters.
Please note that the warranty mentioned here means the warranty for our individual product, and damage provoked by a failure or
defect of the product is excluded from the scope of the warranty.
*This warranty is valid only in Japan.

Application and usage
Our products are designed and manufactured as general-purpose instruments for general industries.
Therefore, our products are not intended for the following uses, and our products used in such a manner are outside the scope ofapplication.
(1) Equipment that is anticipated to greatly affect lives and properties, such as nuclear power generation, aviation, railways, marine
vessels, vehicles, and medical devices(2) Utilities that include electricity, gas, and service water(3) Use in outdoor locations and under similar conditions or environments other than those stipulated in the instruction manual(4) Usage to which considerable safety consideration and attention equivalent to (1) and (2) above need to be given

Service■Scope of service
Because the product price does not include service expenses, such as the dispatch of engineers, we will separately charge for theexpenses in the following cases:(1) Instruction for installation and adjustment and a witnessed test run(2) Maintenance inspection, adjustments, and repairs(3) Technical guidance and technical education(4) Witnessed inspections of products at our factory<<Note>> The product specifications and information in this catalog are subject to change without prior notice for product improvement orother reasons.

●For order placement, contactGeneralagent

Manostar Shop Co., Ltd.

1-2-3 Nishishiriike-cho, Nagata-ku, Kobe City, Hyogo 653-0031
TEL. +81-78-621-7000 FAX. +81-78-621-7788

Manufacturer

Yamamoto Electric Works Co., Ltd.

1-2-3 Nishishiriike-cho, Nagata-ku, Kobe City, Hyogo 653-0031
TEL. +81-78-631-6000 FAX. +81-78-631-6020

SEPTEMBER 2021 YAMAMOTO ELECTRIC WORKS CO., LTD., JAPAN