Installing Voltage regulator
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Topic: Installing Voltage regulator
Posted By: Ron(WA)
Subject: Installing Voltage regulator
Date Posted: 10 Dec 2011 at 10:42am
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I am going to install a new voltage regulator in my D15. It has a generator, not an alternator, and the generator works well. I would really appreciate instructions on the installation process and the do's and don'ts for the installation of the regulator, which mounts on the panel below the battery and in front of the control panel. For example, do I need to polarize the system initially by momentarily crossing the ARM terminal to the BAT terminal before starting. Will I fry the regulator if I accidentally hook it up wrong and cause a momentary discharge through the system (it is a mechanical regulator, not electronic)? Thanks in advance, folks. |
Replies:
Posted By: DougS
Date Posted: 10 Dec 2011 at 11:12am
| Voltage regulators were mechanical. Didn't it already have a regulator? Are you installing something new or is this a replacement? |
Posted By: tbran
Date Posted: 10 Dec 2011 at 12:06pm
| MOMENTARILY TOUCH BATT TO GEN OR B TO G - IF UNIT IS NOT CHARGING CORRECTLY. NEVER TOUCH FIELD. REMEMBER TEACHER TOLD US Girl TO Boy NOT Girl TO Female - However today that illustration would not PC work huh.... |
Posted By: DougS
Date Posted: 10 Dec 2011 at 12:23pm
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Why would he need polarize the generator when he stated that it is already working well, tbran? If it ain't broke, don't fix it. The regulator should have 3 terminals on it. A: armature - this goes to the A post on the generator. F: field - this goes to the field on the generator. B: battery - this goes to your battery. Instead of the battery it would be best if it went to your ammeter, then your battery. Occasionally you will find an L terminal on the regulator. This goes to your light switch. Now, matching the regulator to the generator. That can be tricky. It involves changing the gaps in the regulator. Go ahead and install it as above. Measure the regulated voltage after you finish. If is isn't between 13.8 and 14.5 volts - and yes, the tenths of a volt are important, you'll need to adjust the regular. That gets complicated and takes patience. Let someone else here who has done that explain it to you. |
Posted By: Ron(WA)
Date Posted: 10 Dec 2011 at 1:01pm
| This is a replacement mechanical regulator. The old one got tired. |
Posted By: DougS
Date Posted: 10 Dec 2011 at 1:03pm
| Just do a wire-for-wire swap then. |
Posted By: CTuckerNWIL
Date Posted: 10 Dec 2011 at 6:18pm
Most anything I have read about polarizing a generator mentions doing it after the generator has been disconnected. "Since even a very small current can polarize the shoes, never assume the generator is properly polarized. You must polarize the generator every time it is disconnected or serviced." ------------- http://www.ae-ta.com" rel="nofollow - http://www.ae-ta.com Lena 1935 WC12xxx, Willie 1951 CA6xx Dad bought new, 1954WD45 PS, 1960 D17 NF |
DougS wrote:Posted By: DaveKamp
Date Posted: 11 Dec 2011 at 9:22am
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The regulator armatures DO develop residual magnetisim in, and of themselves, so it's best to flash it (engine not running when you do it, now) then fire her up, and let it run for a while, and babysit the voltmeter. Don't jump on trying to get a 'fine' adjustment until after it's been charging for a while... reason being... residual magnetism in the regulator contact's coil core will 'skew' the output a bit 'till the polarization has settled to match the new environment. There's a great library of DELCO-REMY service bulletins starting with the D-R Standard type two- and three-unit regulators, but I don't have the URL off the top of my head... a google search will probably pull it up... it's an excellent read, and definately something good to have in a reference binder on a shelf in the tractor-shop. |
Posted By: DaveKamp
Date Posted: 11 Dec 2011 at 9:34am
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Oh, and no worries- you won't fry anything... it's very robust stuff, just don't nail it down and hold it... just a short swipe across the terminal is all it takes. Here's an excerpt from the "Regulator Maintenance" paragraph: " 1. Mechanical checks and adjustments (air gaps, point opening) must be made with battery disconnected and regulator preferably off the vehicle. CAUTION: The cutout relay contact points must never be closed by hand with the battery connected to the regulator. This would cause a high current to flow through the units which would seriously damage them. 2. Electrical checks and adjustments may be made either on or off the vehicle. The regulator must always be operated with the type generator for which it is designed. {Dave's note here - This is because there's two configurations of generator- types where the regulator GROUNDS the field (it's internally connected to the gen output terminal) and types where the regulator puts DC power ONTO the field (it's internally grounded in the generator} 3. The regulator must be mounted in the operating position when electrical settings are checked and adjusted and it must be at operating temperature. {This is because the generator's nature is to generate higher voltage as temperature is lower, and the battery's charge demand is skewed by temperature, cranking recovery load, and internal chemistry} 4. After any tests or adjustments to the generator on the vehicle must be repolarized after leads are connected but before the engine is started, as follows: {They say BEFORE the engine is started BECAUSE... if the GENERATOR is somehow polarized backwards, when you start it, there will be 12v coming from the battery, and the generator will try to DISCHARGE the battery with a -12v applied voltage... you'll have a 24v series circuit, carrying a WHOLE LOTTA POWER through wiring which will very immediately become a fuse.} REPOLARIZING THE GENERATOR After reconnecting leads, momentarily connect a jumper between the "GEN" and "BAT" terminals of the regulator. This allows a momentary surge of current to flow through the generator which correctly polarizes it. Failure to do this may result in severe damage to the equipment since reversed polarity causes vibration {they're talking about in the regulator points here} arcing, and burning of the relay contact points. " |