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Rotating light 125 V DC supply

Rotating light 125 V DC supply

Rotating light 125 V DC supply

(OP)
Hi I am looking for a rotating light that can be supplied from a 125 v
DC supply, I can not seem to find one.

In our current installation the following is used

http://www.federalsignal-indust.com/product/371-co...

But these guys don't make 125 v DC anymore,

Any suggestions either I can buy a converter from 125 v dc to 120 V ac ( expecting a suggestion)that could do that conversion, or a replacement that could be powered by 125 v dc.


Thanks in advance.

RE: Rotating light 125 V DC supply

If it has to be a "rotating light", you will probably end up with a 24VDC light and a 125 to 24VDC converter.

If a strobe will do, you can get one that will take 125VDC directly. Here is the first one I found with a brief search-

http://www.galco.com/buy/Edwards-Signaling/97R-MP

I do not know how its performance will compare to the 200 watt sealed beam you have been using.

RE: Rotating light 125 V DC supply

(OP)
All,

Thanks for your response .


Wayne,

You talked-about performance, I noticed that commander 371L at 120 v ac ,200 w sealed lamp has 36000 candela,
On the other hand xenon strobe kight 97 series from EDWARD SIGNALING has 800000 candela,

https://www.edwards-signals.com/index.cfm?pid=276&...

Please see under the documentation section, I thin it's candela are higherprobably a serious kick compared to commander lamp, Am I missing anything ?? Which might tell me that lamp was brighter.

RE: Rotating light 125 V DC supply

My experience is with police, fire and similar emergency vehicles and in that application, brightness is only one aspect of performance. For instance, a strobe beacon will be very "bright" for a brief time when it fires, but completely dark between flashes. The 200W sealed beam, while less powerful, projects a continuous moving beam that (usually)provides a longer flash than a strobe when the beam sweeps across the viewer's vision, and may also reflect from nearby walls, equipment etc. even when it isn't pointed directly at the viewer- the rotary beacon never goes completely dark. Thus, the rotating sealed beam may be a less bright, but more effective attention getting device.

Also worth mention, LED products have become very popular within the past several years. Sealed beams and strobes are close to obsolete in the emergency vehicle business today, mostly due to the LED's power draw and maintenance advantages. My experience is that most people perceive an LED as overwhelmingly bright compared to strobes or sealed beams.

What exactly is your application?

RE: Rotating light 125 V DC supply

(OP)
It is a alarm on controls DC of 125 v for a substation circuit breake
SF6 leakage , so the horn blows and now beacon is not in picture any more, this xenon strobe will flash.

RE: Rotating light 125 V DC supply

I think the strobe will be a reasonable replacement. Even the dullest of individuals should realize that something is wrong given the combination of a horn and flashing strobe.

RE: Rotating light 125 V DC supply

If it is operating off the substation tripping & control battery make sure it will survive when the battery goes on to equalise (boost) charge. It wouldn't be the first time something was carelessly specified and then either stopped working or caught fire when the battery went into equalise. You might also want to consider whether it will be able to operate properly when the battery approaches final discharge.

RE: Rotating light 125 V DC supply

(OP)
Appreciate the caution scotta uk,

In case I have to do a layman's comparisons, a commander 371L A3
Rotating beacon can do fine for all these years, this .2 amp running strobe should do just fine.
Is this comparison acceptable ?

RE: Rotating light 125 V DC supply

Old fashioned beacon motors are just copper and iron, so while it might rotate a bit faster than normal if the voltage is high and the lamp might not last as long, it will still work. Conversely at low voltage its rotation will be slower and the lamp be less bright but it will still work. Electronic stuff just tends to die if the voltage is too high.

Ideally you want something which is happy with the supply between about 90V and 160V or so. I actually like catserveng's suggestion - use a wide-range switchmode power supply to derive a stabilised 24V from the station battery and run your beacon from the 24V.

RE: Rotating light 125 V DC supply

(OP)
I looked at edward signalling website 97 series single strobe flash
It can handle from 72- 125 v DC and can handle extra 10 percent over.

I think this should make the cut ?

RE: Rotating light 125 V DC supply

In my experience equalising can require up to about 2.5V/cell which would be about 150V. You might get away with it.... or not! smile

RE: Rotating light 125 V DC supply

Why not use a resistor in series to drop the voltage? The strobe will probably draw less power than the beacon it replaces, so the dissipation in the resistor will not be unreasonable. And a conservatively rated resistor is robust, proven technology.

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