ECN Forum Forums General Topics of the Trade General Discussion Area Voltage spike source?

I can only provide partial answers.

The ballasts are made by Advance, and many were sent back to Advance for examination.

It is Advance that tells me that components failed on the input side, suggesting exposure to high voltage.

Ballasts are rated for the nominal voltage of the circuit; that is, a 120v rating on a circuit that measures 124 - 125v.

The pad mounted transformer serves seven customers, all in the same building. 4 are retail spaces (mini mart, fast food, butcher shop, novelty shop), 2 offices, and the house meter. Each tenant has their own HVAC (house does not have HVAC).

All problems so far seen are on circuits served by the house meter, and on the lighting circuits. 10 circuits, and seven involve the outside lights - leaving the alarm panel, and two I can't recall offhand.

Any chance the taps on your transformer need bumped down a step or two? I wonder if the peak voltage is excessive in the wee hours of the morning or if there are automatic tap changers that effect your area.
Joe

My guess is these Ballasts are being spiked / surged, from one (or more) of the Tenants connected to the same Service Section / Transformer.

The noise is bursting outwards, and affecting the HID Ballasts at Night when the Site / Parameter / Area Lighting is on - which is, of course, fed from the House Panel, through the House Meter, which is tapped from the Meter Section, common to the Tenants'.

As stated before, the "Electronic HID Ballasts" are relatively new in the Industry, and are still going through a kind of "Public Sector, In-Use Beta Test" thing, in order to "Find The Bugs".
Expect a more stable version in a few more years.

The same was experienced when Electronic Fluorescent Ballasts for Linear fluorescent Lamps, were first introduced to the Industry.

Failure rates were high in the first few years (some were higher than ever expected!).
After time, the Manufacturers gathered failure data, tried newer approaches, and eventually came up with stable versions used today.

If the failures are not _DIRECTLY_ resulting from TVS/S generated by the Tenants, or other Customers, the problems may be from the operation of the Lamp, applied to an erroneous Ballast design - or due to unstable Line Voltages.

To be specific;
* What are the Lamps' Wattage + Type?
I kind of think they are 55 Watt Metal Halide, Pulse Start Lamps.

* Is the Power Factor > 0.95?
If you are not sure, just list the Line Input Amps, and the Lamp's rated Wattage, for a given Ballast.

* The Measured 124-125VAC: was this taken at daytime, or night; and were the Lights on or off; and was the test done at the first fixture, last fixture, or at the Panelboard?

I am really curious about this scenario! Want to find out what is going on, not only because I want to help get this problem under control, but also because we have a few Clients requesting HIDs driven by Electronic Ballastry.

I have been explaining the "Learning Curve" for failure rates experienced with newer Technologies, and suggesting them to wait a few more years for the Technology to improve, so their investments are worthy - not a significant loss from maintenance nightmares due to large failure rates.

Lastly, the issues of failure may be from the Lamp's operation, and / or the Ballast's counter-action with the Lamp.

Simply, the Lamp may be causing the Ballast to "Push-Back" Spikes and/or Surges of Voltage - either as high levels of Harmonic Distortion (and the "Line Input" components are suffering from this noise), or the overall Power Factor is leading too much (< 0.7), resulting in a High Voltage being "Pushed-Out" of the Ballast, which damages the Line Input Components.

Please let me know what Lamps are used, the Wattage, and the Ballast information, so I can research this.

Also, if you have the opportunity to open one or two damaged ballasts, get some pictures of the fried components, plus mark down the Identifier marked on the PCB / Component; then post the information / pictures here.
Alternately, just make note of the smoked Components (ID, location on board, description of the Component, etc.), and post the info. here.

Good luck.

Scott

Just curious if there is any update info?? Did the Data Logger reveal anything?

I have not received any feedback from the PoCo ... but I have continued to have problems with one 'fancy' thermostat. While one would expect the 120/24v transformer to have protected the thermostat, at this point I'm not ruling anything out.

Failures of other components seem to have ended. The replacement ballasts, photocell, and timer are doing well.

Thanks for letting us know up to the date with the info what is going on there.

I am tempting to suggest the idea about the low voltage set up I don't know if it worth the money or not but get auto reguated transfomer it may able cure up some of the surges.

Merci,Marc

Absent either proof of a regular problem ... or further equipment failures ... I am tempted to let it all slide.

If I see other problems arise, my plan is to instal some manner of surge suppressor at the panel. I note that they are available in all manner of sizes ... any suggestions as to how to size them?

what size the exsting service is there now ? and yeah there are few diffrent size you can use some you will actally use in place of breaker space if have room otherwise a remote mount will work.

Merci,Marc