3 Phase Diesel Generator Repair

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joe glaum Participant Join Date: May 2012 Posts: 2	3 Phase Diesel Generator Repair 05/03/2012 5:30 PM
	Hello I am attempting to repair a 1972 Delco model E6802H3 150KW diesel generator with a 6-71 detroit engine. We purchased it as a working unit and it quit putting out power one day when we started it in the morning. Had a generator repair shop come look at it, they said the regulator was bad (mod # 3H18020AR) I found a refurbished one. He also said that the diodes should be replaced, sure enough when I pulled the back cover off one had exploded, he had no sources for parts and I haven't been able to find anyone who knows anything about these older units. The diode is a do-5 base. Can't get a p/n off it cause the original circuit board was painted over, diode painted, tried to get paint off but no luck p/n gone. Went to tech department at local electronics supplier, also no luck. Looking for an electronics engineer who knows these circuits or can reverse engineer a good one? Thanks for any info you can provide. joe
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	Pathfinder Tags: 3 phase electronics engineering Generator

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SolarEagle Guru Join Date: Mar 2007 Location: by the beach in Florida Posts: 31859 Good Answers: 1751	#1 Re: 3 phase diesel generator repair 05/03/2012 6:06 PM
	http://www.nyco-systems.com/Products/part/index.php?Part=3H18020AR http://www.plccenter.com/Buy/DELCO%20PRODUCTS/3H18020AR __________________ All living things seek to control their own destiny....this is the purpose of life
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4R Plus Services Member Join Date: Jun 2011 Posts: 8	#2 Re: 3 Phase Diesel Generator Repair 05/04/2012 6:58 PM
	Hello Joe, I have been in the generator repair business for a long time. would you like to tell me the brand of your alternator( marathon, stamford, leroysomer?). I am maintaining a detroit diesel driven generator in our place with stamford alternator. If you can provide me with the model of the alternator and the actual KW or KVA rating as stamped in the alternator nameplate, I can help you find the pn. Also, there is a local company here who are selling Universal voltage regulators, their regulators "fits all" generators. Should you be interested, send me a PM.
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HiTekRedNek Guru Join Date: Oct 2006 Location: 44.56024"N 15.307971E Posts: 6944 Good Answers: 253	#3 Re: 3 Phase Diesel Generator Repair 05/05/2012 5:44 AM
	If you know the voltage and current that the diodes are required to handle, a generic replacement can be found readily.If it is part of a full wave bridge, to provide DC for the regulator, a replacement should be easy to find.Do you have a schematic of the regulator, or can you tell me where this diode is used.Are there 4 diodes in a square, or diamond configuration?A close up photo of the board would help a lot.I have a lot of experience repairing "Ghost Boards" with no information to go on. Hope I can help. __________________ "A man never stands so tall as when he stoops to help a child." "Never argue with a stupid person.They will drag you down to their level and beat you with experience"
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jarongaus Participant Join Date: May 2012 Posts: 2	#4 Re: 3 Phase Diesel Generator Repair 05/05/2012 12:46 PM
	HI Joe, If you can send me some pictures of the module itself, with emphasis on the diodes connections and also the panel that shows the excitation voltmeter/current if any, so that I can have a better idea of the voltage of the field, or if you have this info, it would be better. Second, I need to know if the diodes are direct or reverse, check the one that is good if any, and the the connections to it, meaning the wiring coming to the module and its polarities on the diode. In fact you may have a combination of both. Once I have this info, I can tell you what diodes to use if you want to do it yourself. Also I need to know if all diodes are mounted on the same heatsink. Make sure to tell me how many power diodes are used on this module. You can e-mail me directly at . Cheers. Jacques. CR4 Admin - email address removed From the CR4 Rules: Do not post phone numbers or email addresses. The CR4 Admin will delete all phone numbers and email addresses posted in threads or comments. You can share this information via the CR4 internal messaging system.
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joe glaum Participant Join Date: May 2012 Posts: 2	#5 Re: 3 Phase Diesel Generator Repair 05/21/2012 3:40 AM
	REPAIRED... The rotating rectifier was needing the SCR'S replaced and 2 out of 6 diodes replaced, the generator repair service that came out blew up these parts doing some kind of excessive testing that overloaded the circuit. also replaced the regulator. I made an educated guess as to the volt and current to use in the circuit of the new parts and it works great, 40 amp on the diodes and 35 A on the scr's. 460 volts 226A 60 Hz
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