Phase loss protection relay

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tx2step

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I'm installing some large paint booths with 10 to 15 HP 208V 3 phase blower motors.

The owner is concerned with having phase loss (anti-single phasing) protection.

Do any of you have any recommendations on a reliable and cost effective method to do that?

Have any of you had any good or bad experience with 3-phase monitoring relays?

Maybe something like Time Mark #258 or #2644?


http://www.time-mark.com/products.php?id=16&category=3-Phase Monitors

http://www.time-mark.com/products.php?id=24&category=3-Phase Monitors

http://www.time-mark.com/products.php

Any other suggestions?

(corrected web site address for #258)
 
If you haven't bought the motor starters yet, buy them with electronic overload relays. Many of them have single phase protection built into the overload realy.
Don
 
Don, Thanks for the reply!

The starters were provided with the equipment and have standard overloads.

Do you think I could get the electronic overloads for those starters? (I don't remember the brand, I'll have to look)

If so, do you think those work better and/or cost less than the Time Mark relays?

Approximate relay cost:

Time Mark #258 is about $80

Time mark #2644 is about $150 and has DPDT contacts, so more than one starter could be protected by it. It also has an adjustable time delay on the response time from 0.2 seconds up to 20 seconds to reduce nuisance tripping from momentary voltage fluctuations.

Both models also protect against phase reversal, too.

I haven't used any of these products, so I don't know how well any of them work.

I know that you are supposed to be able to protect from single-phasing by sizing the overloads very close to the measured running amps (instead of to the nameplate amps), , or to use time delay fuses also sized very closely to the measured running amps, but that seems like it would be time consuming to get dialed in accurately, and might cause just as much nuisance tripping.

Anyone else have any experience or opinion on this general question?
 
If you already have the starters I would guess that the stand alone phase loss relay would be more cost effective.
Don
 
there are many manufacturers of phase loss relays --- the one i used was "timemark". they have one you can actually control the voltage at which the relay will trigger -- adjustable. brake the coil voltage through the relay's auxillary contacts -- connect the voltage sensing line leads to the line side of the starter---------------------
 
Don and Charlie -- thanks for the response!

Charlie, I'm looking at a Time Mark #2644 which is adjustable for the voltage it triggers at, and is also adjustable for the time delay before it triggers.

Did the ones that you installed work OK?

Any problems or nuisance tripping?

Thanks!
 
phase protection relay

phase protection relay

Square D provides this with its telemeqanique I think french overload units (electronic) as opposed to the eutectic solder pots type. The problem with these units is that in fringe areas of power distribution the relays are too sensitive and will dump motor relays when peak demand pulls the voltage down too much on one leg and if the motor being protected is a circulation pump for a heating system it can cause a series of safety trips which can cause havoc with a buildings utility systems. in these cases it is better to go to eutectic solder pots or bimetalic heaters which are more amerage than voltage sensitive. If it is protecting a motor the the most economical way to do it next time is to order the starter with the electronic overload unit in it. you can also probably get one of these units reasonably cheap on ebay and if the range is too high i think you can make up to about 3 passes thru the donut sections for example if you are protecting a 5 amp fla motor you could use a 15 amp relay unit but will have to make 3 passes thru each donut so the unit sees the addidtive amperage from 3 passes sparky
 
phase protyection relay

phase protyection relay

You could also make a homemade job with 3 icecube relays one each powered by each phase and the contacts wired in series to the coil .
 
Quoque - Thanks for the response!

Relays like the Time Mark ones also incorporate phase reversal protection, and also monitor phase angle to detect voltage regeneration from a motor that is running with one phase out.

So with good relays, there is apparently more to it than just straight voltage measurement.

A motor that's running with one phase out will act like a generator and produce as much as 95% of the proper voltage on the missing phase. You apparently have to have some other technology included to detect this condition reliably.

I don't have any experience with them yet, so I don't know how well they work. I was hoping that someone here could tell me, as well as anything to watch out for when using them.
 
Steve, thanks for the reply!

What model of SqD relays do you mean?

Have you used them and had good luck with them?

About how much do they cost?

Did you look at the Time Mark relays that I have pagemarked in my OP?

How do they compare with the SqD model?
 
The appearance and basic function of the Time Mark design is very common.

Manufacturers that I can think of off the top of my head, include (and I will miss some):

Grey case - Time Mark
Orange case - ATC/Diversified
White case - Square D (old style)
Black case - SYM/COM
Blue case - RK Electronics
 
Jim, Thanks very much for the reply!

Do you think the Time Marks are relatively effective?

Are there other relays in the $150 price range that work better?

What are the pros and cons to using these types of relays on starters that right now only have the standard heater type overloads?
 
Experience or Opinions Please?

Experience or Opinions Please?

Does anyone have any experience with these types of relays that they can relate?

If not, does anyone have any opinion as to their effectiveness or other pros or cons?

I'd like to have some idea if and how well they work before I embarrass myself with this client.

Any help anyone can give will be appreciated!

Thanks!
 
A new situation!

A new situation!

Last friday the local school called. Lots of stuff wasn't working, all over the school. Come quick!

The school is 208/120Y

The local POCO had lost one phase in that part of town. A large substation transformer had smoked! The phase stayed off much of the day.

Some of the A/C equipment may have been damaged, it looks like a couple of compressors may have to be replaced.

The school wants to know what can be done to protect their equipment if this happens again.

I'm looking at installing a dozen or more phase loss protection relays of some sort. I still don't have any first hand experience with them, and would really like to hear from some of you guys how well they work before I recommend they pay for me to install over a dozen of them.

Right now, I'm looking at the Time Mark #2644, which includes an adjustable time delay before it triggers. They cost about $150 each.

http://www.time-mark.com/products.php?id=24

Does anyone have any other equipment or approach they would recommend instead?

Does anyone have any first hand experience with the Time Mark relays?

Any pros or cons?

We're talking over a dozen relays at around $150 each plus labor, for a total bill of maybe $3,000 to $4,000. I'd like to make sure I'm right before I recommend that solution to them.

Any help, experience, suggestions or opinions will be greatly appreciated!
 
Re: Experience or Opinions Please?

Re: Experience or Opinions Please?

tx2step said:
Does anyone have any experience with these types of relays that they can relate?

If not, does anyone have any opinion as to their effectiveness or other pros or cons?

I'd like to have some idea if and how well they work before I embarrass myself with this client.

Any help anyone can give will be appreciated!

Thanks!
Click to expand...

I have used several different brands along with the electronic OL relays others have spoken about. They all worked just fine. Can't tell you much on pricing because we get such wildly varying pricing on stuff.

The only issues I have had is in one case a while back voltage variations caused one of the units to trip more than was convenient (at least we sort of figured it was voltage variations). There was some kind of setting that could be adjusted on that particular unit that was not real well documented that resolved that particular issue.

I can't say I have a lot of experience using them, and being as I don't see the equipment they get put on everyday I can't tell you a whole lot about how they perform in the field. I can tell you our customers are not shy and would and do tell us most emphatically if they have serious problems, and I have not heard of any other than the one.
 
I just realized my square d link didn't work. You have to click "R", then click "Relays", and about the 4th or 5th one down is phase loss relays. They have two types. The MPD is the more sophisitcated one.



They also protect against phase reversal. I have used these, but can't really say how they have worked. They are kind of like surge suppressors- If they do their job the equipment keeps working, and you can't really say if they have helped, of if there just haven't been any phase losses or surges.

Two problems I had with these: you have to hook the phases up in the correct order, or it won't turn on the load.

I had one set too high for a 200HP motor. (For some reason they come set really high - like more than 90%.) When we tried to start the motor, the voltage would drop, and the phase loss monitor would drop out. The voltage would go back up, and the motor would try to start again. Over and over. About 2 or 3 times a second. It sounded like a jackhammer, and its a good thing we got it shut off within a second or two.

So, you probably want a way for the relay to lock out the starter, and then have a manual reset so you don't have multiple starts.

http://www.squared.com/us/squared/c...5256A3A007091D7/$file/productsa2zFrameset.htm
 
These are three phase loads, right? I think the square d units are 3 phase, and probably won't work on single phase.

STeve
 
I used some once that had a time delay built in before they would restart.

Not real cheap, but had all kinds of bells and whistles. I put them on some well pumps.

<add link>
http://www.symcominc.com/catalog.html



steve66 said:
I had one set too high for a 200HP motor. (For some reason they come set really high - like more than 90%.) When we tried to start the motor, the voltage would drop, and the phase loss monitor would drop out. The voltage would go back up, and the motor would try to start again. Over and over. About 2 or 3 times a second. It sounded like a jackhammer, and its a good thing we got it shut off within a second or two.

So, you probably want a way for the relay to lock out the starter, and then have a manual reset so you don't have multiple starts.

http://www.squared.com/us/squared/c...5256A3A007091D7/$file/productsa2zFrameset.htm
Click to expand...
 
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