Omega RD-MV100 Series User Manual page 58

2.6 Remote Control Wiring (/R1, Option)
Input Specifications
2-12
Item Specification
Input signal Voltage-free (dry) contact, open-collector (TTL or transistor)
Input conditions ON voltage : Less than or equal to 0.5 V (30 mA DC)
Leakage current in the OFF state : No more than 0.25 mA
Signal duration : 250 ms minimum
Input type Photocoupler isolation (one side common)
Internal isolated power source (5 V ±5%)
Dielectric strength 500 VDC for one minute between input terminals and earth ground
terminal
For details related to the control and input types, see section 10.7.