What's the difference between cold loop test and hot loop test?

instrumentation

#1

1.Cold Loop Check
This is an electrical continuity check to confirm wiring integrity from control panel’s terminal block to the field instrument. Please note that field cabling starts from field instrument and goes through Junction boxes and marshaling cubicle to reach termianal blocks of the control panel

2.Hot loop check
After successful cold loop check, each I/O is subjected to hot loop check. In this testing entire loop functionality is checked by simulation of the signal with power up from DCS or PLC
1.Calibration range
2.Activation of inputs / outputs / Field switches / Solenoids
3.PLC/DCS register updates
4.SCADA updates