PR55-47-2CR reads about 0.45 mA on both channels

Hardware
1

Hi,

We have an NCD PR55-47-2CR 2-channel 4–20 mA receiver connected to two SICK PBT vacuum transducers. Here are some information for context:

Receiver:

  • Firmware 10
  • Battery 3.28 V / 98.56%
  • Radio communication and Node-RED packets are working normally

Current readings:

  • CH1: ADC 665 / 0.45 mA
  • CH2: ADC 676 / 0.46 mA

Both channels are physically connected. I disconnected and reconnected the two M12 plugs, checking their keyed orientation, but the readings did not change.

Since 0.45 mA is also the value we normally see on unused channels, both loops appear open or unpowered.

I will attach some photo for evidence of:

  • Node-RED payload
  • field installation and transmitter photos
  • internal photos of the receiver (ignore the radio MAC visible in the older internal photos, as the radio module was replaced later)

The internal connectors and ribbon cables appear seated, with no visible damage.

What could be the issue?

Thank you!

2

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6

Hello @davidemagno let me ask you;

  1. Did the sensor send correct current data at any point?
  2. Did you configure any of the sensor parameters?
  3. Could you share how did you perform the connection between the M12 connector and the SICK PBT transducers please?
7

Hi @Eduardo_Mtz thanks for taking care.

  1. For this specific 2-channel receiver, I have not yet confirmed a valid reading during my recent tests. The installation was already present before I started managing it, so it may have worked correctly in the past, but I do not currently have a verified historical test showing valid 4–20 mA values from these two specific transducers.
  2. No change in default parameters was made. The radio module was replaced previously, and the radio/network settings were restored so that the device could communicate with the gateway again. The receiver is now transmitting normally to Node-RED. Default calibration values are:
  • Low calibration: 68805
  • Mid calibration: 68724
  • High calibration: 68714
  1. Not sure about this point but i can take some picture if needed, what do you need exactly to see? thanks
8

Hi @davidemagno thank you for the information, I would like to double check the connection between the NCD current loop receiver and your SICK PBT Transducers, how is the connection? what diagram or pin out did you use for connection?

Thank you.

9

When the sensor reports a reading like this, it indicates that there is a connection issue