Troubleshooting Extreme Temperature Readings with Accsense Installation

For the Accsense A2-05 Wired LAN Pod upon Initial Installation

If you’re seeing extreme temperature readings using the Accsense A2-05 Temperature Data Logger, this problem can be diagnosed and resolved relatively quickly. Although rare, this issue causes users to see high-temperature readings in the range of 240°C, and usually indicates a broken wire, not that the probe itself is damaged. For example, this can occur when a probe cable has snagged after a freezer or fridge has been moved.

Diagnosis:

When you first install an RTD temperature probe on your A2-05 wired pod, you can go online to view the current temperature in order to determine that the pod installation has been completed properly.

If the reading is positive 240°C or -240°C, then one of the probe wires is either disconnected or broken within the probe or the cable itself.

Check Wiring:

To troubleshoot this issue, open the back cover of the data logger and inspect all three connections:  first visually, and then by tugging on each wire. If any of the wires are disconnected, push down the corresponding connection lever and re-insert the wire into the terminal block. Then pull on each wire individually to ensure that the connection is good.

Test the Probe:

If everything is wired properly and you still get extreme temperature readings, then it will be necessary to test the condition of the probe itself. First, open the back cover and uninstall the probe from the terminal block by pressing down on the three levers together and pulling the wires out from their connections. Remove the probe from the A2-05 assembly. You’ll need an ohmmeter or a multimeter to test the condition of the RTD probe. The RTD probe has one wire of a unique color and two wires of a different color. The multimeter should be set for a range of 0 to 200 ohms. We’ll be taking three separate readings:

The first will be across the two similarly-colored wires. This reading should be between 0 and 2 ohms (for an RTD probe with a 10-ft cable).

We’ll take the next two readings between the uniquely colored wire and each of the two similarly-colored wires. The two readings you receive should be approximately 100 to 125 ohms each, and they should match one another to within a tenth of an ohm (0.10).

For Additional Support:

These steps should resolve the issue in the vast majority of cases. However, if after performing these tests and reinstalling the probe, you still receive incorrect temperature readings, call Accsense Technical Support at 800-956-4437 for assistance or email us at [email protected].