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Last year I upgraded our generator diesel, 24kw to work off our off grid Outback system. Basic Chinese engine and alternator, Deep Sea controller, put together in AZ
Unfortunate I have a voltage imbalance once under load. Have spent too much time eliminating all other possibilities and as of today am as sure as sure can be that the problem is isolated to this generator. I can hook my smaller backup into the system without any imbalance.
So if anyone knows, I need a reference for someone who knows generators and would know what and how to test so I can report back to the manufacturer on the mainland. Of course if such person can also fix it, that might be even better.
Thanks
David
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Who made the back end? Balmar or leece neville (prestolite) .... find the schematic for your back end (usually online - search by back end model number.
Here is a link to a Stamford (cummins) guide check out the fault / diagnosis section:
https://www.cumminsgeneratortechnologies...nual_8.pdf
Power off - use an ohm meter to measure resistance of the windings ..check and see if one of the output legs are open. That would be the first place Id look - after checking for high resistance in the connections to the genset.
If you hit a wall - buy me lunch and Ill swing by with my test kit - (best if after you get the manufacturer prints)
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"Basic Chinese model engine and alternator"... What method is utilized for idle control? Tension spring or an electronic ignition/engine speed (diesel version) sensor and servo based idle controller? If spring tension controlled, they tend to succumb to the elements (rust) out here and lose tension and bring the idle speed to generate below voltage when under load. A new spring set will typically solve the issue otherwise... it's may be in the servo or sensor circuit or something else.
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Most of the chinese imports being "Hinos" ....with Leece or stamford back ends (or copies) came with complete oem rebuild kits and hand cranks .....grin
In the 70's they were going for $400.00 top of the 12 kw units out there
http://www.alibaba.com/product-detail/20...55245.html
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Thanks Bullwinkle
Don't know manufacturer but I do have the literature.
Yesterday an electrician friend checked the windings and as I recall ohm reading were fairly consistent and nothing alarming.
I just sent you a test email.
I'll put the stuff together and email this afternoon.
Lunch and local brew would be a bargain.
David
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quote:
Originally posted by Wao nahele kane
"Basic Chinese model engine and alternator"... What method is utilized for idle control? Tension spring or an electronic ignition/engine speed (diesel version) sensor and servo based idle controller? If spring tension controlled, they tend to succumb to the elements (rust) out here and lose tension and bring the idle speed to generate below voltage when under load. A new spring set will typically solve the issue otherwise... it's may be in the servo or sensor circuit or something else.
Have to check, but guessing mechanical. Engine has no problem cycling up and down with load The DSE7220 control panel shows the engine is running good but the L1/L2 voltage goes out of balance. I can confirm this imbalance anywhere else along the system. Yesterday time spent with generator hooked directly into my main distribution panel and measured in about any configuration we could fathom - all imbalanced. Same tests repeated with Ridgid 8000 in place and no imbalance.
David
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From dealers website:
Generator Alternator Specification
Brushless Alternator
Four-pole revolving field with drop proof screen protected
Self exciting self regulated design
High-quality lubrication sealed for long bearing life
IP21 protection Standard
Complies with VDE0530, IEC34, NEMA MG1-22,CSAC22.2-100 AND AS1359
AVR 120V/ 240V
ALTERNATOR DATA
Model Number TFDW-24
Rated Power 24KW
Rated Current
100 amps @ 240V
200 amps @ 120V
Rated Frequency 60HZ
Rated Speed
1800 Rpm
Power Factor 1 for single phase
.8 lagging for three phase
Phase Connection Single or Three Phase
Excitation Method Brushless
Voltage Regulation AVR
Poles 4 (L1,L2,N,G)
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Interesting... I use 2 gen sets also a Ridgid 8000 as a backup and my Miller Bobcat as the primary. I seldom use the Ridgid 8000 it has less than 100 hours and it crapped out on me and gave the same under voltage reading when trying to charge my PV system. I had to order a new idler spring set for it which solved the problem. I ordered a few sets as back up. The Miller has had no issues thus far but uses electronic control for idle and not the spring set. Hope you get it figured out, it's typically something minor that screws them up.
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L1-L2 imbalance would indicate something else. I'd perhaps try to isolate the faltering leg. Can you switch over to 120v charge and test run it under 120v charge load? Test each 120 leg individually and see if one gives you an issue under load?
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Okay after considering it a while, you only have a L1, L2, N, G poles. Unless there is a winding problem then the issue is phase time. The charge controller needs input to be in a range of 60 cycles per second +/- x cycles per second. If your idle speed places your alternator outside this range then there will indeed appear to be a leg imbalance to the Charge controller that's expecting the 60 cycles per second range. This leads back to engine idle control speed. It may appear to idle up and down to the load but that doesn't mean it's within the proper cycle range. If it's out of sync of the 60 cycles per second expectation it will create an power imbalance between itself and your charge controller/inverter. The inverter/charge controller should not accept the generator current if this is the case and give you an under current, over current warning indicator.
