Jump to content

Smoking alternator


Sthoin

Featured Posts

Having bought an inverter and washing machine before upgrading alternator and batteries, I'd planned that this shouldn't be a problem if I use the cold wash option that the washing machine has, thereby not heating any water. This was approved as a good interim solution by the boss. So I made the assumption (yes I know what assumptions are) that running the engine whilst running the washing machine would help provide the necessary amps, I fired up the engine before starting a cold wash cycle. Monitoring the inverter, I can see a 200-400W flowing as we fill and start the cycle. Then (on a cold wash) this jumps to 1700W. The alternator does not like this. After a few seconds we got a lot of heat and smoke! Turn off the washing machine, and run a rinse and spin cycle without problems (20-400W). The alternator quickly cools down and runs normally. On a second occasion when I think the incoming water was warmer, we got through approx 3-4 minutes of 1700W, before reducing back to it's non-heating 200-400W operation, and no smoke, but lots of load from the sound of the engine having to work harder. It's a Beta 35 with a standard (65A I think) alternator, and I currently have 300Ah of batteries. Any ideas on how I can run with the existing set up - just run on the batteries for the 3/4 minutes of heavy load perhaps (I think that's about 150Amps from the batteries)? And of course advice on an updated set up - alternator, batteries. Update both? What size? Would be much appreciated. Many thanks....

Link to comment
Share on other sites

I have a controllable thermostatic valve that fills the machine with water at a set temperature.

 

Obviously we have to wait until we have a calorifier full of hot water before using the washing machine, but then we can set 30/40/50 degree water and fill the machine with this.

 

This means the high power heating element doesn't switch on (much) to heat the water which is what uses most of the power.

 

Are you sure you were using the cold wash setting correctly?  The cold wash button on ours prevents the heating element coming on at all.

Link to comment
Share on other sites

Sounds like even on the cold setting, the washer is heating the water to some minimum temperature. Simplest solution would be to add a kettle of very hot water through the soap drawer as it is filling, thus taking the overall temperature above the threshold for heating.

Link to comment
Share on other sites

In theory an alternator will self limit for current so should not burn itself out but will run hot. 

 

Are the batteries well charged to start with and holding their charge properly.

 

Was it smoke or stem? If steam from condensation then maybe it is to be expected, if smoke then maybe an alternator strip and clean out might be an idea.

 

May be fit a mixing valve to the inlet so you fill with a combination  of hot and cold water so you leave the machine set to cold but fill with warm water from the valve and calorifier. If you can find a manually adjusted valve it would save wasting hot water to do the rinsing.

Link to comment
Share on other sites

You didn't say if it was 12v or 24v. If its 12v more like 200A given the efficiency of the inverter, shape of the waveform, voltage drops so the alternator is working almost into a short circuit. It won't last long! I don't think 300Ah is enough for that set up.

Link to comment
Share on other sites

Thanks for all the good advice, I'll give the "add hot water a go", see if in the meantime an alternator service might give us a little more reassurance... and look at a thermostatic valve (fortunately I have hot water into the washing machine cupboard, so shouldn't be too difficult).....

2 minutes ago, Mike Adams said:

You didn't say if it was 12v or 24v. If its 12v more like 200A given the efficiency of the inverter, shape of the waveform, voltage drops so the alternator is working almost into a short circuit. It won't last long! I don't think 300Ah is enough for that set up.

Thanks for that advice. A last resort, as I'd like the batteries to last a little longer yet. What capacity do you think would handle the 200A for 3-4 minutes? When I come to upgrade. It would be good to know it could cope with this if it needs to.....

Link to comment
Share on other sites

11 minutes ago, Tony Brooks said:

In theory an alternator will self limit for current so should not burn itself out but will run hot. 

 

Are the batteries well charged to start with and holding their charge properly.

 

Was it smoke or stem? If steam from condensation then maybe it is to be expected, if smoke then maybe an alternator strip and clean out might be an idea.

 

May be fit a mixing valve to the inlet so you fill with a combination  of hot and cold water so you leave the machine set to cold but fill with warm water from the valve and calorifier. If you can find a manually adjusted valve it would save wasting hot water to do the rinsing.

I definitely think it was smoke! Maybe some muck on the alternator burning off as it gets a lot warmer than usual (note to self. Clean the alternator.... not that it's covered in muck, mind you)

Link to comment
Share on other sites

8 minutes ago, Sthoin said:

Thanks for all the good advice, I'll give the "add hot water a go", see if in the meantime an alternator service might give us a little more reassurance... and look at a thermostatic valve (fortunately I have hot water into the washing machine cupboard, so shouldn't be too difficult).....

Thanks for that advice. A last resort, as I'd like the batteries to last a little longer yet. What capacity do you think would handle the 200A for 3-4 minutes? When I come to upgrade. It would be good to know it could cope with this if it needs to.....

Sorry. 12v.....

Link to comment
Share on other sites

10 minutes ago, Sthoin said:

Thanks for all the good advice, I'll give the "add hot water a go", see if in the meantime an alternator service might give us a little more reassurance... and look at a thermostatic valve (fortunately I have hot water into the washing machine cupboard, so shouldn't be too difficult).....

Thanks for that advice. A last resort, as I'd like the batteries to last a little longer yet. What capacity do you think would handle the 200A for 3-4 minutes? When I come to upgrade. It would be good to know it could cope with this if it needs to.....

It’s fairly standard to have 4 110Ah batteries when a big inverter is installed, ie around 440Ah. Before we got lithium batteries we had 450ah of lead acid and it would run a 2kw electric kettle without any problems.

Link to comment
Share on other sites

4 minutes ago, Sthoin said:

I definitely think it was smoke! Maybe some muck on the alternator burning off as it gets a lot warmer than usual (note to self. Clean the alternator.... not that it's covered in muck, mind you)

 

If it is dirty it will be inside it, probably all over the diode heat sinks. More likely if you have a dog or can on board, if a drive belt shredded in the past or there was once an exhaust leak.

Link to comment
Share on other sites

Thanks, that's very useful. I think an upgrade from 3 X 100Ah to at least 4 X 120Ah is a good start....

2 minutes ago, Tony Brooks said:

 

If it is dirty it will be inside it, probably all over the diode heat sinks. More likely if you have a dog or can on board, if a drive belt shredded in the past or there was once an exhaust leak.

No exhaust leaks. No shredded belts. But we do have a dog.....

Link to comment
Share on other sites

If the alternator is a few years old it will have oil, dust, fur and belt debris inside. Its not unusual for then to smoke when treated to a heavy load especially if not running fast enough.

I run my engine foe a while before washing then the water is hot and the batteries well up. The thermostatic blending valve is set to 45 degrees, the washer to 40 degrees and the heater then doesn't come on providing I run a little hot water off first to get the cold out of the pipe.

Link to comment
Share on other sites

Just now, Tracy D'arth said:

If the alternator is a few years old it will have oil, dust, fur and belt debris inside. Its not unusual for then to smoke when treated to a heavy load especially if not running fast enough.

I run my engine foe a while before washing then the water is hot and the batteries well up. The thermostatic blending valve is set to 45 degrees, the washer to 40 degrees and the heater then doesn't come on providing I run a little hot water off first to get the cold out of the pipe.

Thanks, running the engine at a higher speed, and a thermostatic valve seem to be the best solutions. We'll be moving later in the day. I'll try some higher revs and a kettle of warm water to see the effect.....

Link to comment
Share on other sites

You didnt mention state of charge of batts before firing up washer.

we used to make sure our batteries were pretty fully charged before firing up washing machine, and the advec had done 3 cycles. If not the belts would smoke, as the system tried to charge the start battery, and the 500 ah bank and run the washer.

That was with a 110 amp alternator and an advec just to add to the fun.

Link to comment
Share on other sites

Just now, roland elsdon said:

You didnt mention state of charge of batts before firing up washer.

we used to make sure our batteries were pretty fully charged before firing up washing machine, and the advec had done 3 cycles. If not the belts would smoke, as the system tried to charge the start battery, and the 500 ah bank and run the washer.

That was with a 110 amp alternator and an advec just to add to the fun.

Batteries where about 85%. I have a second alternator for the start battery, so that shouldn't be a problem. Today I'll be trying later in the day when the solar should have given me closer to 100%... Good point that it may be the belt, not the alternator itself smoking...

Link to comment
Share on other sites

FWIW I understand that a typical maximum alternator temperature is around 150C but can be exceeded at the risk of shortening the life. Some quote close to 200C. I know you can burn yourself on an alternator that has been operating close to its maximum for a short while. 150C is more than enough to make oily residue smoke,  especially as the doiod pack is likely to be hotter than that.

Link to comment
Share on other sites

1 minute ago, Tony Brooks said:

FWIW I understand that a typical maximum alternator temperature is around 150C but can be exceeded at the risk of shortening the life. Some quote close to 200C. I know you can burn yourself on an alternator that has been operating close to its maximum for a short while. 150C is more than enough to make oily residue smoke,  especially as the doiod pack is likely to be hotter than that.

Thanks to all the wonderful and very prompt advice, I think I'm gaining a much better understanding of what is happening, and that is more valuable to me than any amount of salesmen telling me I need a new alternator, new batteries or a new boat. Thanks!

Link to comment
Share on other sites

A quick update - engine set to 1400 rpm, a kettle of hot water added at the start of the cycle, and no heating attempted by the washing machine, no smoking from the alternator, and a load of washing completed without problems. 

 

Thank you to everyone who contributed to the solution!

  • Greenie 4
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.