2.3 Input Signal Wiring

Measuring Input Wiring

Thermocouple input

b –/B +/A

Extension leadwire

Resistance temperature detector input

b –/B +/A

Leadwire resistance:

10 max./wire. The resistance of the three wires should be equal.

b

B

A

DC voltage input, 1-5V input, and ON/OFF input b –/B +/A

– + DC voltage 1-5V

ON/OFF

DC current input

 

 

b

–/B

+/A

Shunt resistor

 

 

Example: For a 4 to 20 mA

+

input, a shunt resistor of

250 Ω ± 0.1% can be used to

DC current

convert to 1-5V input.

 

 

Note

RTD input terminals A and B on the dot model are isolated on each channel. Terminal b is shorted internally across all channels. However, for 3 legs isolated RTDs (/N2 option), input b is also isolated for each channel.

2-8

Page 52
Image 52
Omega RD100B manual Measuring Input Wiring, Input Signal Wiring, DC current input +/A Shunt resistor