I have a Siemens CP-30 that creates a ‘trouble’ condition when the building’s boiler fires up. The boiler and the FACP are on the same subpanel.
Some time ago I installed a surge protector (similar to those at http://obviously.com/1482/Whole-House-Surge-Protectors Guide to Whole House Surge Protectors ) to protect the boiler motors and FACP. Have others seen the described condition and solved it? I have an idea of an approach, but would love to hear from others before spending time messing around.
I do not have detailed knowledge about a Siemens CP-30. However, I have some questions and suggestions.
What kind of ‘trouble’ condition? More details would be helpful.
Oil fired boiler? Old ones have motors that can throw a lot of electrical noise back on the power. A newer one may have SCR controls. If not filtered these can also throw a lot of noise back on the power. Maybe the boiler manufacturer offers a filter package that can be added.
Have you measured the neutral to ground voltage at the FACP when the boiler is running? Anything over .7 volt is a problem. Measure at boiler start up and running. A peak capturing meter is best for this. Or a scope.
Any chance to change the FACP power feed to a different power panel? Does the building have emergency power? If yes, is the panel the FACP is fed from an emergency panel? The electrical engineer who specified the FACP in that location also could be consulted. He can design a filter using a series reactor and a capacitor for the boiler. Or get the FACP power source changed.
Surge suppressors often are not much help in these situations. Their clamping voltage is 100 to 200 volts above the peak value of the 120 volt circuit. That is 170 volts peak or 340 volts peak to peak. The noise hash from the boiler is much below those levels.
I’m remote from the site, so getting details has been hard.
It’s an oil filed boiler.
There’s a water to air heat exchanger that might actually cause the problem.
The FACP was installed in 1972: everyone involved has retired and/or died.
The building has a manual switchover propane fired generator.
The boiler/fans are far higher amps than the panel, so I’d rather put a UPS on the panel.
The surge protector was installed to protect against lightning damage, and was not expected to condition the power.
A UPS involves an extra set of batteries which detract from system reliability.
There are a number of motors in the boiler room, it’s beyond my scope to add snubbers to them all ( Snubber - Wikipedia ).
A budget power conditioner on the FACP feed is a possibility as I suspect brownouts are at the heart of this.
What model of power conditioner might be suitable for hardwiring?
The idea behind the UPS was to act as a power conditioner.
Does the trouble not reset when power goes back to normal? I assume it’s getting under voltage whenever the boiler kicks on which is tripping the panel. I’ve never had to deal with power conditioners, but someone in remote rural areas might have more experience needing them.
A panel that old could have internal power supply problems. That should be tested also. I replaced quite a few filter capacitors in 2001 panel power supply modules over the years. Electrolytic capacitors dry out in time and their ability to filter the power diminishes.
I recently repaired the clock/timer board in my 30 year old microwave oven. The 2,200 microfarad cap was down to 1,700. There were two 100 microfarad caps. One was down to 3 microfarad and the other was below 1 microfarad. New microwave for $8.16 at Radio Shack.
Another possibility is a degraded capacitor with a high ESR (series resistance). Note this is a linear supply, so it’s actually far less sensitive to bad capacitors compared to a newer unit with a switching power supply.