Thermistor and pressure switch on multicore cable

[shkim2000]

The package consisting of motor and pressure switch will be supplied by vendor. The thermistor is fitted in the motor and motor starter is supplied by us. For the purpose of minimizing cable installation, I consider to one multicore cable from starter to thermistor in the motor and then another cable is installed between motor terminals and pressure switch(for interlocking motor starting).
Is it O.K. if thermistor and pressure switch are used on one multicore cable ?

 

[Skogsgurra]

It depends. If the switch works with low DC voltage (like 24 or 12 V DC) and there is a diode or snubber in the circuit. You needn't worry. But if the switch works directly with motor voltage or anything like 100 - 400 V AC, then most Electrical Codes do not allow it. And it can lead to false triggering (or no triggering) depending on what type the thermistor is.

And - of course - do not put motor voltage and thermistor wires in the same cable. Unless you find a cable that was designed purposely for that (like a machine-tool servo cable or similar)

 

[shkim2000]

It is still not clear to me. Here is more information.
The control power of starter is AC 220V and thermistor relay and pressure switch are driven by AC220V. The thermistor is used for tripping when high winding temprature of motor.
Needs more explanation.

 

[powerjunx]

obviously, thermistor is very sensitive temperature sensor. when it is included to a multiconductor cable together with the power supply line, a line disturbance will affect the accuracy of your sensor, heat build up along the line that also affects it.

in practice a high current carrying wire lines is separated from the instrumentation cables.