sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Security, Alarms and Paging Bogen amp keeps tripping reset

This customer has had a paging system in place for many, many years. Some of the horns I installed, some by others (and they used a different speaker). I replaced the Bogen TPU60 5 years ago, because it had quit working after the previous 2 decades. The company plays background music through the system, and overhead pages when needed.

During the last couple of weeks, the amp has tripped it's built-in reset breaker. By the time I get there, I can't tell if the amp was hot or not. They claim no one has done any wiring or added any speakers. Resetting the reset breaker and everything works for a few days or a week, until it trips again.

I don't have an impedance meter, nor know how to use one. The wiring is old and mostly in a moist greenhouse environment. It splits off here and there a couple of places. It will be a nightmare to trace out and test. But what am I looking for? Reading each leg with an ohmmeter for shorts, high opens, ???

I'm thinking a bad horn or corroded wiring/connection?

Thanks for any direction.
Jim

An impedance meter is really the way to go. The Tpu 60 is a 60 watt amp you said they have horn speakers are they SPT 15's or something similar? Is it possible someone upped the wattage draw on the speakers? I've seen customers up the Spt 15's to the max of 15 watts is that possible? Does it trip after they make a page or just randomly shuts down? Are you wired for 25 or 70 volts?

If you know how to use a DMM, you know how to use an impedance meter. Without the impedance meter and a ground fault check, you can't eliminate the amplifier itself as the problem. Yes you will be looking for short circuits, ground faults, and overloaded lines (although this requires the impedance meter). Is there any hum or noise on the BGM source?

I vaguely remember, back in the K-Mart days, we used to find that some rogue employee would think they knew how to install speakers. Two wires, right? Or, worse, the black tape instead of speaker nuts would come loose and ground itself to the ceiling grid.

As the others have said, an ANALOG impedance meter is a nice tool to own. Turning up the volume (a Pyle PCM60 runs less than $100 on the secondary market or you could drive to Ohio and take an amp or two off my shelf). The problem is that you want to equip yourself with all the tools before you go to the job, or be very close to the site. Without that, look for corrosion in your moist environment and try to cut the load in half. Once you lift the speakers from the grid, you can meter them to ground and look for low resistance faults to ground on the legs you split off. You may find an odd resistance reading that doesn't match the others. Or, you'll probably find that bad boy in the middle of your string :-)

Good luck.

BTW the new amps actually have Bluetooth receivers and MP3 inputs for BGM and MOH.

Carl