In the Apex's display menu structure there is an option called Probe Exp (short for Probe Expansion); it is not available in the classic web interface or through APEX Fusion because it is rarely used.

ProbeExp.jpg

The purpose of the Probe Exp option is to provide backward-compatibility with a legacy/pre-Apex module called a PX1000.

This option should only be set to On if a PX1000 is connected. If a PX1000 is not used, then this option MUST remain at the default setting of Off (disabled).

Probe Expansion does not apply to or affect the use of probes of any type which are connected to an Apex or to PM1, PM2, or PM3 module.

If this option is set to On and a PX1000 module is not connected, the #3 and #4 switch inputs on the Apex/Apex Lite will appear to randomly bounce between OPEN and CLOSED.

If you have inadvertently enabled Probe Exp, turn it off, then reboot the Apex:

  1. Navigate to System->Misc Setup->Probe Exp
  2. Press the center button to change it to Off
  3. Press the Exit button
  4. Scroll up to Net Setup
  5. Press the center button
  6. Scroll up once to Restart
  7. Press the center button to reboot the Apex.

Note: The Probe Expansion option is not present in the Apex 2016 model, in the Apex Jr, or in Apex Classic/Gold/Lite models which are running firmware versions higher than 4.40.