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6-3 Analog OP-05
Please refer to § 4-2 F500 ~ F504
* OP-05 Set at Analog 4 ~ 20mA
If you add a 250Ω resistor , the output will be 1V to 5V (4~20mA)
This resistor must be large enough for proper power consumption.
Use the following formula: W = I ² ×R
where
W: Power I: Output Current
R: Resistor
If a 500Ω resistor is used , power consumption will be :
W = (0.02) ² × 500 = 0.2 when the Output Current is set to 0.2mA
The resistor should have a power greater than "0.5" (w = 0.5) and have a very low temperature coefficient. In
this example power consumption is "0.2" and thus, the 500Ω resistor is adequate.
Setting Output Current
IOUT = IZ + ( weight / capacity ) * ( IM - IZ ) (if 2<= IOUT <=22 mA)
IOUT: Output Current IZ: Output at ZERO (F501) IM: Output at Maximum Capacity (F502)
Example: A weighing system has a Maximum Capacity of 10,000kg.
If you need the Output current to be 4mA at ZERO display, and 20mA at 1/2
Maximum Capacity then:
IM = capacity / simulated) ×(IOUT - IZ) +IZ
IM = 10000 / 5000 ×(20 mA - 4 mA) +4 mA = 36 mA
When Output at Full Scale is set at 36mA, and Output Current at Display ZERO is set at
4mA, then at 1/2 Capacity (5000kg) the Output Current will be 20mA.
※ NOTE: The Maximum Output will be saturated at 24mA.
Range 4 ~ 20mA (Possible: 2 ~ 22mA)
Resolution Min. 1 / 3000
Temp.
coefficient
±(0.015% / ℃of rdg+
0.01mA)/ ℃
Max.
resistance
load
Max.500Ω
Output Circuit:
OP-05 Inside※ Resistance R≦
500Ω