Just wondering what everyone else has been seeing for failures and how often they are seeing them for hot socket events. Also what are you procedures when handling them?
I know at MP we are seeing a fairly steady stream come through in the summer time. Our policy is to dispatch someone to investigate a hot socket alarms 24/7. The hot socket alarms come into our OMS system and automatically open trouble tickets for us. Most of the time the failures are what you would expect to find like a bad jaw or loose connection. A few times it has been more troublesome for us to track down. We have had where the connection to the breaker on the other side of the wall was bad and the cables heated up enough to set the meter alarm off or the breaker in the socket itself. We have also seen where drip loops aren’t correct the cable got water down in it. The cable then proceeded to corrode internally and be the source of the heat. We have also had a very small number of false alarms due to the sun baking a meter on a dark wall. I know further south this is an issue but not so much up here. We did find a work around for this though because the alarm from the meter contains a temp reading from a sensor at the base of the meter and at one just behind the register. If the sunlight caused the issue the one by the register is warmed than the one in the back. A failure type issue is seen as the back one getting warmed first.
Our new meters have more alarming capability and alarm due to rise in temp over a certain time or if the temp sensor in the front vs the back is has too much of a difference. When this switch was made we noticed an increase in the number of alarms right away. We also noticed most of the alarms we go on now don’t usually have signs of physical damage to the meter so it makes tracking the failure reason a little tougher but its always been correct in showing an issue.
What is everyone doing to investigate? I know I have wanted to use thermal cameras but haven’t been able to get the funding put together so we just use the temp guns to gather temp readings on each lug and we also tension test the lugs with a TESCO gap indicator. This usually results in finding the source of the problem and either we fix it if we own the socket or send the customer a fix it letter. We have also tried the TESCO safety clips to add tension back to the bad jaws we find but we have had mixed results. They don’t’ always stay on and they don’t work on all sockets. We have had some of the safety clips break in half when the meter is reinstalled.
Our Hot Sockets tend to be meter brand specific – Itron single phase meters being the worst. We have been using GE I-210 single phase meters and I have yet to have 1 come in with the back of the meter completely melted – Like I see with Itron –
We probably have about 20 Hot Sockets per year – And we don’t find them until the module stops reading (TWACS AMR) – and crew will go out – notice the meter is melted and either change a lug or put in a new loop – and problem is fixed.
I have heard mixed reviews of the TESCO jaw tester – we will not be using it – Our philosophy has been more reactive compared to proactive on this issue –
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