HAI Phase Coupler failure?


Is it common for an HAI phase coupler to fail? I have over 30 HAI devices (mostly HAI switches, but a few SAI outlets and buttons) and OmniPro with one phase coupler. It has been running fine for many years. Over the last year I have been having comm issues. The HAI Omni PIM seems to have fewer comm issues to devices on other phase but still, consistently, can't control a few devices on other phase... always the same ones. With Upstart and a USB PIM it is MUCH worse to devices on other leg. When I plug in on one phase I see extremely strong signals and no noise to devices on the same phase... but devices to the other phase have signal around 4... still no noise. If I plug in on opposite phase, then all those devices have excellent signal strength. The only thing that changed last year was the pad mount transformer at the street got swapped out. I have tried moving the phase coupler to another location and no difference. Red light glows, but have no way of knowing if it is working or not. Since Upstart does not show ANY noise anywhere on the system, is it possible the phase coupler died? If so, what is best/cheapest one to replace it with? Thanks!
They have a capacitor, so can wear out. Replace it with an active repeater if you can. They work so much better. Not 100% compatible with SAI switches, but if you don't need to program them, you'll be fine.
I just happened to notice mine was dead completely. There are two protection diodes and a 5V regulator that are cooked and dead shorted. I was afraid to spend the money and time replacing those parts only to find out the rest is bad because of their failure. So I bought a used one that does power up, but still won't see or repeat any signals.


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