Not exactly a Seagull topic,but as there are some engineers and electricians on this site-
Can you run an automotive alternator in any direction,or will it only work when driven as intended ?
I am fitting a small diesel engine into the engine room of my boat to power a 65 amp alternator so that i can charge batteries
with out having to start up the main propulsion engine.
Drive to alternator will be by vee belt,so in a nut shell in what direction will it have to rotate.
Any help on this appreciated.
fitting Alternators
Moderators: John@sos, charlesp, Charles uk, RickUK, Petergalileo
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RAY SWANN
- Posts: 57
- Joined: Sun Nov 08, 2009 1:35 am
- Location: International space station (toilets blocked again)
fitting Alternators
SOME DO, SOME DONT,THOSE WHO DONT, DO A BIT
Re: fitting Alternators
I don't think you can run it in the wrong direction.
One thing the diodes and the other will be the fan, or you could just face the alternator in the other direction.
For more info
http://web.media.mit.edu/~nathan/nepal/ ... nator.html
One thing the diodes and the other will be the fan, or you could just face the alternator in the other direction.
For more info
http://web.media.mit.edu/~nathan/nepal/ ... nator.html
Re: fitting Alternators
There is a faint bell ringing in my long distant past that suggest that I have seen a belt in figure 8 configuration that would reverse the rotation. How to stop it wearing out, I don't know.
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Collector Inspector
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- Location: Perth Western Australia
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Re: fitting Alternators
Automotive Alternator?
99% of them rotate clockwise from the front. They will only work that way.
Yes, Diode bank and field dictate that rotation for the 99%
They do not go backwards. Nothing happens that is.
I forget which but the other 1% go the other way. (DUH)
Try early Hitachi and Nippon Denso.
The Jap ones are really small, about 16 amps and self rectify. They could go either direction. The cooling fins/fan looked different to any normal alternator. You will pick it at once, very odd shape.
They were single wave DC with two positive terminals on the rear depending which way they turned from memory. They were not rated at 14 volt, more like 13 volt.
1960s - early 1970s
Performance was adequate for what they were.
B
B
99% of them rotate clockwise from the front. They will only work that way.
Yes, Diode bank and field dictate that rotation for the 99%
They do not go backwards. Nothing happens that is.
I forget which but the other 1% go the other way. (DUH)
Try early Hitachi and Nippon Denso.
The Jap ones are really small, about 16 amps and self rectify. They could go either direction. The cooling fins/fan looked different to any normal alternator. You will pick it at once, very odd shape.
They were single wave DC with two positive terminals on the rear depending which way they turned from memory. They were not rated at 14 volt, more like 13 volt.
1960s - early 1970s
Performance was adequate for what they were.
B
B
A chicken is one egg's way of becoming others
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RAY SWANN
- Posts: 57
- Joined: Sun Nov 08, 2009 1:35 am
- Location: International space station (toilets blocked again)
Re: fitting Alternators
OK
Thank you everyone,I have a new Lucas alternator I intend to use,so will make sure it rotates clockwise.
Good lead with plenty of information Keith,have saved it in favorites.
The alternator fitted to the main engine only puts out 13.5v,but according to the engine hand book that is correct.
Thanks chaps
Ray
Thank you everyone,I have a new Lucas alternator I intend to use,so will make sure it rotates clockwise.
Good lead with plenty of information Keith,have saved it in favorites.
The alternator fitted to the main engine only puts out 13.5v,but according to the engine hand book that is correct.
Thanks chaps
Ray
SOME DO, SOME DONT,THOSE WHO DONT, DO A BIT
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RAY SWANN
- Posts: 57
- Joined: Sun Nov 08, 2009 1:35 am
- Location: International space station (toilets blocked again)
Re: fitting Alternators
Sorry!
Just one more question.
Will it damage the alternator if it runs with no current to the energising terminal?
In other words do I start the engine then switch on current to excite alternator, or
do I have to start engine with the alternator excited.
I am bored at home,its snowing,its still four months till spring,canal is frozen over,
stuff is too expensive on *bay.
None of my motors need any work.
Her indoors has decided that the shed is for "storing things and not a workshop".
This is the only project I have till spring
I am so bored I have even been up and double insulated the loft......
Just one more question.
Will it damage the alternator if it runs with no current to the energising terminal?
In other words do I start the engine then switch on current to excite alternator, or
do I have to start engine with the alternator excited.
I am bored at home,its snowing,its still four months till spring,canal is frozen over,
stuff is too expensive on *bay.
None of my motors need any work.
Her indoors has decided that the shed is for "storing things and not a workshop".
This is the only project I have till spring
I am so bored I have even been up and double insulated the loft......
SOME DO, SOME DONT,THOSE WHO DONT, DO A BIT
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Collector Inspector
- Posts: 4196
- Joined: Sun Jun 29, 2008 4:32 am
- Location: Perth Western Australia
- Contact:
Re: fitting Alternators
Turn the ignition on, volts to field.
Start engine, volts to field off.
Engine runs, on ignition, volts to field.
By the way.................I have never seen snow.
Take a pic of your front yard for me?
B
Start engine, volts to field off.
Engine runs, on ignition, volts to field.
By the way.................I have never seen snow.
Take a pic of your front yard for me?
B
A chicken is one egg's way of becoming others
Re: fitting Alternators
Disconnecting the field Excite wire should cause no damage. Alternators with internal regulators need only a brief jolt of current after the engine starts to energize the field coil. Once this happens, the half-wave rectifiers (diode trio) take over and produce current for the field directly from stator output.
If its a basic 3-wire alternator it has the regulator powered by one of the smaller connector wires. The other wire provides some current to the field to assist with the initial turn-on. So, if you disconnect these smaller wires then the thing will stay off and you can use a smaller toggle switch to turn it off.
I hope you get Excited
If its a basic 3-wire alternator it has the regulator powered by one of the smaller connector wires. The other wire provides some current to the field to assist with the initial turn-on. So, if you disconnect these smaller wires then the thing will stay off and you can use a smaller toggle switch to turn it off.
I hope you get Excited
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Ian Malcolm
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- Joined: Thu Mar 30, 2006 11:42 am
- Location: London, ENGLAND
Re: fitting Alternators
Actually as an alternator has slip-rings for the field, and the diodes don't care, there is NOTHING electrical to stop it running either way. The problem lies with the fan and the brushes. If the brushes are skewed to trail for longer life they will wear faster if rotation is reversed and they are 'pushing'. If they point directly at the shaft center there shoudn't be a problem The fan is designed to run one way only and wont adequately cool the alternator if running backwards.
Re: fitting Alternators
What, go out in the coldCollector Inspector wrote:
Take a pic of your front yard for me?
B
Have no front yard.
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Charles uk
- Posts: 4972
- Joined: Wed Feb 27, 2008 4:38 pm
- Location: Maidenhead Berks UK
Re: fitting Alternators
Now I know why us Poms dislike the males of the Australian sub species
"never seen snow"
Just wait for the post telling us it's 38 degrees centigrade outside, as the icing on the cake!
"never seen snow"
Just wait for the post telling us it's 38 degrees centigrade outside, as the icing on the cake!
Make it idiot proof and someone will make a better idiot.
Re: fitting Alternators
Automotive Alternator?
99% of them rotate clockwise from the front. They will only work that way.
Yes, Diode bank and field dictate that rotation for the 99%
They do not go backwards. Nothing happens that is.
I forget which but the other 1% go the other way. (DUH)
No from an electrical point of view it does not matter which way they spin.
They generate Alternating current ... and thats the same which ever way you look at it.
Consequently it makes no difference to the rectifier diodes (and regulator.)
HOWEVER the design of the fan blades may well dictate the direction in which it must run. They only one of mine accessible at the moment would not cool properly if run counterclockwise. The other two are buried under about !8" or so of snow.
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RAY SWANN
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- Joined: Sun Nov 08, 2009 1:35 am
- Location: International space station (toilets blocked again)
Re: fitting Alternators
For the benefit of the Australian members who have never seen snow,I am listing a few
snow facts.
Snow was invented by sir Issac newton,shortly after he invented gravity.
(Some people did say that snow had been around for years,but until he
invented gravity had remained in the sky)
At first snow was available in most colors,but it was decided to only supply it in white
to avoid confusion with Teflon.
Teflon invented by another famous Englishman sir Cliff Richard was only produced in black,
as Teflon and snow are very similar.
Snow was exported to many countries e.g. Canada,Russia,but was never exported to Australia
as they were mostly ex convicts and could not afford it.
With orders filled and declining snow sales, large amounts left in stock had to be dumped at the poles.
I hope this will clear up any misunderstandings over snow.
Ray
snow facts.
Snow was invented by sir Issac newton,shortly after he invented gravity.
(Some people did say that snow had been around for years,but until he
invented gravity had remained in the sky)
At first snow was available in most colors,but it was decided to only supply it in white
to avoid confusion with Teflon.
Teflon invented by another famous Englishman sir Cliff Richard was only produced in black,
as Teflon and snow are very similar.
Snow was exported to many countries e.g. Canada,Russia,but was never exported to Australia
as they were mostly ex convicts and could not afford it.
With orders filled and declining snow sales, large amounts left in stock had to be dumped at the poles.
I hope this will clear up any misunderstandings over snow.
Ray
SOME DO, SOME DONT,THOSE WHO DONT, DO A BIT
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Charles uk
- Posts: 4972
- Joined: Wed Feb 27, 2008 4:38 pm
- Location: Maidenhead Berks UK
Re: fitting Alternators
Ray please do not give away too many of our national secrets, look what happened when we taught them a few of our ball games & exported a few Morris minors & A35's.
Now they make Minaro's & Ute's that we can't afford to fill the fuel tanks, & our biggest English motor manufacturer is Morgan!
Now they make Minaro's & Ute's that we can't afford to fill the fuel tanks, & our biggest English motor manufacturer is Morgan!
Make it idiot proof and someone will make a better idiot.
Re: fitting Alternators
Alternators
Some Honda fitted automotive alternators turn anticlockwise. They were fitted to their anticlockwise rotating engines. These were east/west config engines. This layout was used to eliminate the need for a backgear in the trans when with the front of the engine lies to the left. The other jap manufacturers solved the backgear prob by lying the front of the eng to the right, much more sensible.
Honda fitted alternators are about 50~65Amp with self internal regulation from memory. Could be hitachi, but, entirely sure. Honda electronic control systems are often TEC brand. Would pay to dismantle any secondhand unit & fit new bearings & slip rings & brushes as a minimum.
This'll solve your fan & brush direction on your lucas. Suggest talking to your local wrecker
Rex
Some Honda fitted automotive alternators turn anticlockwise. They were fitted to their anticlockwise rotating engines. These were east/west config engines. This layout was used to eliminate the need for a backgear in the trans when with the front of the engine lies to the left. The other jap manufacturers solved the backgear prob by lying the front of the eng to the right, much more sensible.
Honda fitted alternators are about 50~65Amp with self internal regulation from memory. Could be hitachi, but, entirely sure. Honda electronic control systems are often TEC brand. Would pay to dismantle any secondhand unit & fit new bearings & slip rings & brushes as a minimum.
This'll solve your fan & brush direction on your lucas. Suggest talking to your local wrecker
Rex