This article will describe some troubleshooting steps for diagnosing input signal issues with our digital input panel meters. This includes counters and timers.
APPLICABLE PRODUCTS
- PAX series
- CUB series
- T48C series
- T48T series
PRE-REQUISITES
One of the above listed digital input panel meters.
IN THIS ARTICLE
This article will offer some troubleshooting advice to help diagnosis input signal related issues on our digital input panel meters.
Troubleshooting steps and questions.
First, verify that the input is programmed properly in the unit. If it is programmed properly, follow these troubleshooting steps:
Verify the sink/source dipswitch or jumper is in the correct position for your sensor.
-Sink if the sensor is creating a path to common.
-Source if the sensor is providing voltage to the input.
* Note the CUB4, CUB5, CUB7, and PAXLCx00 user inputs are sink only.
Verify the input is wired properly.
-The input common is 0V.
-The input is where the voltage will be applied (source) or removed (sink).
Disconnect all other inputs and outputs.
- Many units do not have isolated inputs
- First, verify that the input is not being inhibited or held in reset (Timer applications).
- Units without isolated inputs require that all of the inputs share the same common. Ensure that all of the inputs share the same common or add external isolation.
Verify the input is at the proper voltage potential. Disconnect the input and monitor the voltage between the input and input common.
-Sinking inputs should measure a voltage (1.25-3.6VDC for CUB4 and CUB7 units, 5VDC, 12VDC, or input power voltage for CUB5 units)
-Sourcing inputs should measure 0VDC
Verify the input is changing the voltage levels.
* this may require an oscilloscope.
-Sinking Input:
-When the input is off, you should be measuring the same voltage as the previous step.
-When the input is on, it should be reading 0VDC.
-Sourcing Input:
-When the input is off, you should measure 0VDC.
-When the input is on, you should be measuring the voltage that the sensor outputs.
Test the input with a jumper wire or switch.
-Sinking Input:
-Place a jumper wire or switch between the input and common.
-Sourcing Input:
-Place a jumper wire or switch between a DC voltage source and the input.
ADDITIONAL INFO
Links to product manuals
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