ELTS Controller Stuck in Emergency
The information in this post is provided to assist in troubleshooting. Perform work at your own risk. ENSURE ANY POWER FROM DEVICES HAS BEEN DISCONNECTED BEFORE SERVICING ANY EQUIPMENT. If you do not feel comfortable performing the work, please contact us or your local service center. Be aware that ETC and its Affiliates are not responsible for any damage or injury caused by service of our products by anyone other than us or our authorized service providers, and such damage is excluded from the product’s warranty.
Symptoms/Issue
ELTS system is not switching out of emergency
Explanation of Issue
Very often this is an on-site issue. There are three likely causes:
- One or more of the transfer switch control relays has failed (ice cube relays)
- One or more phases have gone missing, dropped below expected voltage, or is unstable
- A fire alarm signal has gone bad somewhere in the system and is causing the controller to remain in emergency. If the fire alarm signal is not used, check that the jumper in the ELTS cabinet is landed correctly
Solution
Before sending the controller to ETC, check the following:
Steps 1 and 2 should be checked with the system powered OFF
Step 3 requires the system to be live to make measurements. If you are not comfortable taking voltage measurements on a live electrical system, please contact an electrician
- With the system powered OFF, check the ice cube relays for appropriate resistance values (see related links, ELTS 1 Ice Cube Relays article)
- Check the fire alarm. If the system is using the fire alarm signal, a station could be sending a false signal to the controller, forcing it into Emergency. If the fire alarm signal is not used, check that the jumper is landed correctly
- Check all phases for the correct voltages appropriate for your system (Phase A Normal, Phase A Emergency, Phase B Normal, Phase B Emergency, Phase C Normal, Phase C Emergency)