Navigation

You are here: Home / Messages / Electrical / Rectifier/regulator

Rectifier/regulator

Up to Electrical

Rectifier/regulator

Posted by andy_bone at February 03. 2017

I am about to fit an Alton starter to my '72 Commando. At the moment it is fitted with a 3-phase SRM 180 watt alternator. This will be replaced by the Alton 2-phase, (single phase?) 150 watt unit.

I fitted an RGM modern rectifier/regulator a year ago, obviously for a 3-phase system. Can this be used? I read on a different blog that one just connects the two output wires of a single phase system to any two of the three spade connectors and all would be well.

Question: is that true?

Any advice welcome.

Andy Bone

Re: Rectifier/regulator

Posted by john_holmes at February 04. 2017

Yes its true, plus gives you a spare half of a rectifier if a diode fails.

Re: Rectifier/regulator

Posted by les_howard at February 04. 2017

Yes. It will work, but like for like power inputs in terms of rated output (watts) will stress the diodes slightly more, fortunately your new alternator has a lower output....Put simply eg: 180 watts (3 phase) rectified by 3 sets of diodes gives an average of 60 watts each whereas 180 watts (if single phase unit) divided by 2 sets give 90 watts each...but at 150 watts (your new alternator) it equals 75 watts per diode pair... but still 25% more...it will probably be OK however though but invalidate the guarantee.....which probably has expired anyway?

Les

Re: Rectifier/regulator

Posted by christopher_winsby at February 04. 2017

Previously andy_bone wrote:

I am about to fit an Alton starter to my '72 Commando. At the moment it is fitted with a 3-phase SRM 180 watt alternator. This will be replaced by the Alton 2-phase, (single phase?) 150 watt unit.

I fitted an RGM modern rectifier/regulator a year ago, obviously for a 3-phase system. Can this be used? I read on a different blog that one just connects the two output wires of a single phase system to any two of the three spade connectors and all would be well.

Question: is that true?

Any advice welcome.

Andy Bone

Buy a new single phase  rectifier/regulator Andover Norton do a 200 watt one.  Keep the 3-phase set together. It may be expensive but how much is an Alton starter set up? That way you  will not be wondering if the old one will last or weather it will be too much load one the diodes. If you are concerned by the cost you can always sell the 3 phase set up. If you knacker the old rectifier/ regulator it is worth nil. That way it is one less chance of letting you down.  It is always better to have spare capacity rather than run on the limit.

Re: Rectifier/regulator

Posted by andy_bone at February 04. 2017

Previously les_howard wrote:

Yes. It will work, but like for like power inputs in terms of rated output (watts) will stress the diodes slightly more, fortunately your new alternator has a lower output....Put simply eg: 180 watts rectified by 3 sets of diodes gives an average of 60 watts each whereas 180 watts divided by 2 sets give 90 watts each...but 150 watts (your new alternator) equals 75 watts per diode pair...25% more....will probably be OK though but invalidate the guarantee.....which probably has expired anyway?

Les

Thanks Les, that is what the blog suggested. I still have the original rectifier and zenor diode so I have backup. I just like the performance of the modern unit. The ammeter needle hardly flickers whatever the revs.
For a few quid one can source a single phase unit. I might in due course sell the SRM alternator with the rotor on ebay, with the rectifier as part of the kit.

Cheers,

Andy

Re: Rectifier/regulator

Posted by alan_osborn at February 04. 2017
You do not have back up with the original rectifier and zener, as the original Zener was only worth regulating up to100W and your new system generates a lot more. The original rectifier might not handle the power either (the modern encapsulated rectifier will handle the power). I would have thought the ALTON would have come with its regulator/rectifier, they usually do and again any under guarantee might be in doubt if any other reg/rect was used. By the way I sell reg/rects that can be used on such a system. A O
Powered by Ploneboard
Upcoming Events
Norfolk branch camping weekend May 12, 2017 - May 14, 2017 — Whitwell and Reepham railway station, Reepham, Norwich NR10 4GA 01603 871694
CRMC Track Parade - Mallory Park May 20, 2017 - May 21, 2017 — Mallory Park,Church Rd, Kirkby Mallory LE9 7QE
Surrey Branch at the Kempton Park Classic Motorcycle Show & Auto-jumble May 20, 2017 09:30 AM - 04:00 PM — Kempton Park, Staines Road East, Sunbury on Thames, Middlesex TW16 5AQ
Tay Valley Branch - lunch meeting May 21, 2017 11:00 AM - 04:00 PM — Ben Lawers Hotel,Loch Tay, Aberfeldy, Perthshire, PH15 2PA
Yorkshire Branch at the Sowerby Bridge Classic Bike & Scooter Show May 28, 2017 10:30 AM - 04:30 PM — The Wharf, Sowerby Bridge HX6 2AG
Upcoming events…
This is Brio Diazo Plone Theme