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CJKEVIN Posted: Apr 27, 2015 04:21 PM	generator/air compressor issues I have a 3 phase 70 kw diesel with a "Delta" or "high leg" style winding on the generator unit. The generator powers two 3 phase 230v 5 horse reciprocating air compressors, and two Graco E-30s (plus all the other stuff). The issue I am having is that if I power the air compressors up after I have my reactors on I blow a motor control board or heater control module in the reactors. My other two rigs with small gas generators do not seem to do this, I can fire up the generator and reactor at the shop, get everything heated up and then turn the air compressor on at the job and haven't ever had any problems with blowing circuitry in the reactor (e-20s on the gas rigs). Any thoughts as to what could do this? I have since installed in-line 3 phase surge protectors on the Reactor power lines coming off of the main circuit breaker in the truck but would like to know what the root cause of the problem may be. I have been told by my electrician that a "Y" wound or "star" wound generator is preferable to a high leg unit when powering computer equipment but I am not sure that this is the problem. Any thoughts? Thanks!
SprayFoamSupply.com Posted: Apr 27, 2015 09:08 PM	Are you powering up both compressors at the exact same time? It would certainly seem that you have enough power, but not alot extra. are your E-30's the 10kw standards, or the 15kw high heat? How much hose on each? I assume that the E30's are wired 3 phase as well? When you have this issue, is the generator bogging down? Generators like clean air and fuel filters, and if they are not serviced regularly, you can only get 2/3's of the power you should be getting. Having the generator wired delta, Y or star doesn't matter in this case. All of the electronics in the E30 are 208-240v so having the high leg doesn't matter in this case, nothing runs off of only 1 leg. In fact, wiring delta is better as you get the full 240v between any two legs instead of 208v. Getting 240v makes your preheaters and hose heat perform 15% better than 208v. George
Randy Taff Posted: Apr 27, 2015 10:51 PM	All of the motor control boards I have seen blown over the last 14 years have either been very old or seen dirty power from guys starting and stopping the generator with the Reactor left on. I would look at the power supply and make sure something is not causing some kind of power fluctuation. An electrician should be able to diagnose this issue without too much trouble. If the board blows when both compressors are turned on then there is your clue. You may need a bigger Gen. If this is an older setup that has worked for a while and is just now having an issue I would look for loose wire connections first.
CJKEVIN Posted: Apr 29, 2015 07:50 PM	This truck was built over the spring of 2014 at our shop. Generator is a 2014 model packaged by Southwest Products. The engine is a perkins turbo common rail diesel, and the generator is a Hanco unit. The generator has no issues running at any time, no load or fully loaded. Fuel filters and air filters are clean. I turn on each compressor separately, wait for the first one to come up to speed, then turn the 2nd one on (about 3-5 seconds between turning each one on). Sometimes when I do this the motors spool up then slow down substantially before spooling back up again (kinda seems like they are stalling, but I have manual backup unloader valves that are always open when I turn on each compressor). This problem is intermittent, and seems to be completely random (though I think it might be related to the fried electronics) Reactors are standard 10kw E-30s. Hose is 300 feet of Graco hose, plus a 10 foot whip on each. The reactors are wired 3 phase The generator does not bog down when i start anything, we have plenty of power for what we are trying to do, as this unit does not have a fresh air system, or any other substantial auxiliary systems. George, That is interesting to know about the advantages of a Delta windings, my electrician did not explain that to me.
CJKEVIN Posted: Apr 29, 2015 08:04 PM	SprayFoamBC, These electronics are brand new, I am thinking it is a dirty power issue as well... Main question is is it a voltage surge that is a result of my air compressors almost stallings, or is it some sort of issue with the delta wound generator unit...? I will add that we (electrician and I) put a device on each of the 3 power wires feeding each air compressor motor and measured a 58-62 amp draw at startup, (turing the compressors on when they were cold, 0 psi tank pressure and manual unloaders open) Is this enough to create a voltage surge that would fry my boards in the reactors? If so, do I have a bad set of air compressors or are reciprocating compressors notorious for this type of thing?
Randy Taff Posted: Apr 30, 2015 07:57 PM	That start up draw seems way way high. My 10hp 3ph 230V unit draws approx 28 amps on start up and runs around 10 amps if I am not mistaken. I think you need to go to a single compressor or larger Gen.
Chicago Spray Foam Posted: May 06, 2015 09:58 PM	Since changing over to screw compressors our random fried items have completely gone away. As a bonus, our fuel consumption has gone way down on our 40kw genset.
CJKEVIN Posted: May 07, 2015 05:36 PM	Sounds like the general consensus around here is that the reciprocating compressors lead to issues, and screws are the way to go. We were originally going to go with a screw on this truck but didn't due to the cost difference, haha now I have fried multiple boards and modules in the name of saving money. Looks like a screw is in the near future for this rig. Thanks for the replies!

Author

Comments

CJKEVIN

Posted: Apr 27, 2015 04:21 PM

generator/air compressor issues

I have a 3 phase 70 kw diesel with a "Delta" or "high leg" style winding on the generator unit. The generator powers two 3 phase 230v 5 horse reciprocating air compressors, and two Graco E-30s (plus all the other stuff). The issue I am having is that if I power the air compressors up after I have my reactors on I blow a motor control board or heater control module in the reactors. My other two rigs with small gas generators do not seem to do this, I can fire up the generator and reactor at the shop, get everything heated up and then turn the air compressor on at the job and haven't ever had any problems with blowing circuitry in the reactor (e-20s on the gas rigs). Any thoughts as to what could do this? I have since installed in-line 3 phase surge protectors on the Reactor power lines coming off of the main circuit breaker in the truck but would like to know what the root cause of the problem may be. I have been told by my electrician that a "Y" wound or "star" wound generator is preferable to a high leg unit when powering computer equipment but I am not sure that this is the problem. Any thoughts? Thanks!

SprayFoamSupply.com

Posted: Apr 27, 2015 09:08 PM

Are you powering up both compressors at the exact same time? It would certainly seem that you have enough power, but not alot extra. are your E-30's the 10kw standards, or the 15kw high heat? How much hose on each? I assume that the E30's are wired 3 phase as well? When you have this issue, is the generator bogging down? Generators like clean air and fuel filters, and if they are not serviced regularly, you can only get 2/3's of the power you should be getting. Having the generator wired delta, Y or star doesn't matter in this case. All of the electronics in the E30 are 208-240v so having the high leg doesn't matter in this case, nothing runs off of only 1 leg. In fact, wiring delta is better as you get the full 240v between any two legs instead of 208v. Getting 240v makes your preheaters and hose heat perform 15% better than 208v.

George

Randy Taff

Posted: Apr 27, 2015 10:51 PM

All of the motor control boards I have seen blown over the last 14 years have either been very old or seen dirty power from guys starting and stopping the generator with the Reactor left on. I would look at the power supply and make sure something is not causing some kind of power fluctuation. An electrician should be able to diagnose this issue without too much trouble. If the board blows when both compressors are turned on then there is your clue. You may need a bigger Gen.

If this is an older setup that has worked for a while and is just now having an issue I would look for loose wire connections first.

CJKEVIN

Posted: Apr 29, 2015 07:50 PM

This truck was built over the spring of 2014 at our shop. Generator is a 2014 model packaged by Southwest Products. The engine is a perkins turbo common rail diesel, and the generator is a Hanco unit.
The generator has no issues running at any time, no load or fully loaded. Fuel filters and air filters are clean.
I turn on each compressor separately, wait for the first one to come up to speed, then turn the 2nd one on (about 3-5 seconds between turning each one on). Sometimes when I do this the motors spool up then slow down substantially before spooling back up again (kinda seems like they are stalling, but I have manual backup unloader valves that are always open when I turn on each compressor). This problem is intermittent, and seems to be completely random (though I think it might be related to the fried electronics)
Reactors are standard 10kw E-30s.
Hose is 300 feet of Graco hose, plus a 10 foot whip on each.
The reactors are wired 3 phase
The generator does not bog down when i start anything, we have plenty of power for what we are trying to do, as this unit does not have a fresh air system, or any other substantial auxiliary systems.

George,
That is interesting to know about the advantages of a Delta windings, my electrician did not explain that to me.

CJKEVIN

Posted: Apr 29, 2015 08:04 PM

SprayFoamBC,

These electronics are brand new, I am thinking it is a dirty power issue as well... Main question is is it a voltage surge that is a result of my air compressors almost stallings, or is it some sort of issue with the delta wound generator unit...? I will add that we (electrician and I) put a device on each of the 3 power wires feeding each air compressor motor and measured a 58-62 amp draw at startup, (turing the compressors on when they were cold, 0 psi tank pressure and manual unloaders open) Is this enough to create a voltage surge that would fry my boards in the reactors? If so, do I have a bad set of air compressors or are reciprocating compressors notorious for this type of thing?

Randy Taff

Posted: Apr 30, 2015 07:57 PM

That start up draw seems way way high. My 10hp 3ph 230V unit draws approx 28 amps on start up and runs around 10 amps if I am not mistaken. I think you need to go to a single compressor or larger Gen.

Chicago Spray Foam

Posted: May 06, 2015 09:58 PM

Since changing over to screw compressors our random fried items have completely gone away. As a bonus, our fuel consumption has gone way down on our 40kw genset.

CJKEVIN

Posted: May 07, 2015 05:36 PM

Sounds like the general consensus around here is that the reciprocating compressors lead to issues, and screws are the way to go. We were originally going to go with a screw on this truck but didn't due to the cost difference, haha now I have fried multiple boards and modules in the name of saving money. Looks like a screw is in the near future for this rig. Thanks for the replies!

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