At times the AT 3600 shows a message “Danger” on the display with a beep sound . What could be the possible reason for this?
There are two possible reasons for this Danger message:
1. There maybe a fault with the AC Interface module. This module contains isolation relays that connect the source to the DUT when required. If these isolation relays become faulty isolation may not occur when an X test is run and this can result in a danger message.
2. Any condition where a node voltage is measured by a test program when there is no voltage expected may result in a danger signal. This maybe due to back emf from a high inductance part or possibly some residual charge from a capacitor. This capacitive charge can be discharged with the use of relays driven from the OUT port, if necessary. Please see Thread 1649 for details on using the User test with OUT tests.
To understand this issue better a program can be written with a single VOCX test and this test run say 20 times to ensure that you do not see a Danger message. This will help to understand whether previous tests in your program are causing a residual charge issue. It will also help to prove whether the AC interface is working correctly.