Customer is connecting PTC sensors to the ATS480 soft start and wants to know how to read the thermal value from that circuit to monitor the actual motor temperature.

The ATS480 allows the connection of PTC or PT100 sensors using the PTC1/AI1, PTC2, PTC3 and COM terminals.

There are several parameters that can be monitored over a network....depending on the type of sensor being used.

• TH1F and TH1A are used only when AI2T=PT100, or 3 PT100

The temperature correspondence used in drive when AI1T=PT100 or 3PT100 are a standardized value. See Spec below :

The Standardized value is available from parameter AI1C: Logic Address 5232.

• When AI1T=PTC, it is not possible to know the temperature. they fixed by the sensors manufacturer, so not configurable by the customer:

PTC must follow our recommendation:

The Physical value of AI1 can be read from parameter AI1C: Logic address 5242.

So, you must to read the value in Ohm then make your conversion in PLC using the curve provided by PTC manufacturer.

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