Overwatch - Faults - Not Passing Installation Tests (OEM lights)

Overwatch - Faults - Not Passing Installation Tests (OEM lights)

Notes
Some EQSS Overwatch kits receive their control signals from scissor control box LED display circuits.
Overwatch kits are engineered and adapted to reliably function as a safety cutout system. Various control signals (within the scissor control box) are carefully considered and then the most reliable ones are chosen to be monitored by the Overwatch system. Sometimes, panel lamps and sometimes panel LED lines are chosen as a reliable signal source. They are monitored and create a trigger event for the Overwatch when they complete a circuit. These sources also have the added benefit of being immediately visible (and thus are usable as a trouble shooting tool). 

Therefore, if during an Overwatch installation test, some function is failing, please look at and observe all control box panel lights. If it's found that some light(s) are not illuminating (faulty on the control board), then this could be the cause of an Overwatch test failing. 

Below is a generic schematic, illustrating the type of circuit being discussed in this Tech Doc:

In the example schematic above, a connection is made for the Overwatch to monitor and sense a logic change. If a fault occurs at the logic chip that drives the transistor and LED, then the Overwatch will not sense a logic change and also the LED will not illuminate. This could be used effectively as a troubleshooting tool. So if the Overwatch is not sensing one of the signals from the EWP control box, then please observe and make sure first, that all control box indicator lights are operational before raising EQSS support requests.

The example above showed control signals sampled from the electronics light drive circuits by the Overwatch. The other approach is a more direct connection to the actual signal lights themselves. Some of the Snorkel machines (for example) have this sort of direct connection. If the light bulb has burned out and the circuit is broken, then the Overwatch is not able to sample the machine's control signals and therefore will fail the Overwatch Setup tests.
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Example of Snorkel RT control box signal lights being used to monitor elevate and drive control signals to Overwatch