Connecting Modbus Probes

Connection order for Pyxis Probes

Pyxis Modbus/Digital probes are connected to THOR Digital Controllers using a single cable. This factory installed cable provides both power and data communications for all inline probes connected to the cable (bus).  All probes are externally connected to the cable. 

Pyxis Modbus probes connect using 5 Pin connectors. Each probe ships with a mating 5 Pin TEE.  TEEs may be connected directly to another TEE to extend the number of probes that can be connected to a single cable. (See Image below).

THOR supports up to 8 Pyxis Modbus probes on any single controller.

When connecting a probe to a TEE or a TEE to another TEE,  be sure to fully seat the threads. Typically hand tightening will be sufficient. Do NOT OVERTIGHTEN, a wrench is not recommended, do not force or cross thread the connector. Line up the notches on the connectors and hand tighten. 

THOR communicates to each probe based on its programmed ADDRESS or PIN (1-8) not the order of installation. The order in which probes are placed on the cable will not impact operation.  This address is also referred to as a "Slave Address".

Probes may be removed and reconnected to the cable at any time. When a probe is disconnected THOR will not be able to read the values and as a result any outputs/relays relying on the probe's data will malfunction.

Be sure to disable or remove any probe dependent Output/Relay PRIOR to removing a Pyxis Modbus probe or changing the address of a Pyxis Modbus Probe!



Please note you may NOT have two probes with the same address on the cable at the same time. This will cause unexpected results and interfere with THOR's operation. 

Please see the video tutorial on adding a Modbus probe for detailed instruction for programing a Pyxis Probe on THOR. 

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