WOC Number and Alternator Paralleling.

[canals are us?]

I have been getting a few quotes on alternator paralleling and reading up the various topics on the subject and using diodes. It goes right over my head!

I asked in my marina an they can use a device that costs £350 plus 200 to fit it which would parallel both alternators and if one fails still have a functional alternator. It was expensive, and so I asked if I could just fit a larger alternator, as think this option would be cheaper.

I currently have a 70A domestic and 50A starter battery alternator. They didn't really know without seeing my engine etc, but thought fitting a larger domestic one was possible and the easier option.

I have sent an email to Beta Marine to ask what is possible with my 1305 engine and they have asked for the WOC number of the engine. Where is this located?

I want to increase the alternator charging output/rate so that it will provide sufficient charge to run my Victron inverter to run the washing machine with the engine running while out in spring/summer.

Many thanks. James.

Edited February 6, 2018 by canals are us?

[Phil.]

WOC number is normally located on a label on the top of the engine and begins with a K.

[pearley]

Mine is on a silver sticker on top of the engine. 

[OldGoat]

This question came up fairly recently and AFAIR the consensus was that there wasn't much scope to increase the size of either alternator. The smaller alternator is quite a tight fit so a physically larger unit couldn't be fitted. In similar vein, although there's probably space for a larger secondary alternator the drive to it may be impracticable (that's why Beta want the Works Order Control number - later engines may have a different drive arrangement). 

Your solution may be to make the alternator(s) work harder with  electronic device(s) and that's what may be proposed by the boat yard. To my mind you need a joint approach, make the alternator(s) work harder by fitting a gadget AND give them / it more batteries to charge so that they work for longer and you have more capacity in the batteries for what you want or need.

 

[canals are us?]

Thank you both, I'll have a look when I have removed the stuff stored in there above the engine boards tomorrow as plan to install the inverter.

James 

3 minutes ago, OldGoat said:

This question came up fairly recently and AFAIR the consensus was that there wasn't much scope to increase the size of either alternator. The smaller alternator is quite a tight fit so a physically larger unit couldn't be fitted. In similar vein, although there's probably space for a larger secondary alternator the drive to it may be impracticable (that's why Beta want the Works Order Control number - later engines may have a different drive arrangement). 

Your solution may be to make the alternator(s) work harder with  electronic device(s) and that's what may be proposed by the boat yard. To my mind you need a joint approach, make the alternator(s) work harder by fitting a gadget AND give them / it more batteries to charge so that they work for longer and you have more capacity in the batteries for what you want or need.

 

As you say it might be impractical due to pulley arrangements etc and loadings on the pulleys. I'll see what they say when I send them the WOC number. It may end up with as you say electronic devices or alternator paralleling.

James

[Eeyore]

35 minutes ago, canals are us? said:

I have been getting a few quotes on alternator paralleling and reading up the various topics on the subject and using diodes. It goes right over my head!

I asked in my marina an they can use a device that costs £350 plus 200 to fit it which would parallel both alternators and if one fails still have a functional alternator. It was expensive, and so I asked if I could just fit a larger alternator, as think this option would be cheaper.

I currently have a 70A domestic and 50A starter battery alternator. They didn't really know without seeing my engine etc, but thought fitting a larger domestic one was possible and the easier option.

I have sent an email to Beta Marine to ask what is possible with my 1305 engine and they have asked for the WOC number of the engine. Where is this located?

I want to increase the alternator charging output/rate so that it will provide sufficient charge to run my Victron inverter to run the washing machine with the engine running while out in spring/summer.

Many thanks. James.

The 1305 (approx 1300cc, 4 cylinder) engine hasn't been sold by Beta for some time.

Some of these earlier engines did use versions of the Lucas A127, so the similar (slightly larger) 90 amp unit could be an option.

Do you have any pictures of the installation?

Steve (Eeyore)

[canals are us?]

14 minutes ago, Eeyore said:

The 1305 (approx 1300cc, 4 cylinder) engine hasn't been sold by Beta for some time.

Some of these earlier engines did use versions of the Lucas A127, so the similar (slightly larger) 90 amp unit could be an option.

Do you have any pictures of the installation?

Steve (Eeyore)

Hi thanks for your reply. 90 amp would be better than 70!

I only have this photo. I can take any needed tomorrow when I clear the area ready to fit my inverter.

James

 

 

[WotEver]

The simplest way to parallel the alternators will be with a VSR - Voltage Sensitive Relay. 

About £35, or these folk will supply a kit with all the cables for a bit more:

https://www.12voltplanet.co.uk/voltage-sensitive-relay-12v-140a.html

[Eeyore]

16 minutes ago, canals are us? said:

Hi thanks for your reply. 90 amp would be better than 70!

I only have this photo. I can take any needed tomorrow when I clear the area ready to fit my inverter.

James

 

 

The one at the bottom of the picture certainly looks like a Lucas A127. The size of the thick red wire; both length and cross sectional area, needs to be determined to see if it is suitable for use with the larger alternator.

The important bit - it's unlikely to make any significant difference to your battery charging, but will help if running the engine to help with large inverter loads.

I would view it as a worthwhile upgrade if being carried out as a service replacement for a failed 70 amp unit.

Steve (Eeyore)

Edited February 6, 2018 by Eeyore

[dor]

26 minutes ago, Eeyore said:

 

The important bit - it's unlikely to make any significant difference to your battery charging, but will help if running the engine to help with large inverter loads.

 

A very significant point and one not realised by many people.  Just fitting a bigger alternator will not significantly decrease your charging time.  This is because the charge current is controlled by the battery not the alternator. The only way to increase the charging current is to increase the charging voltage.

You can have a 100A alternator, but I bet, with 50% discharged batteries of 440Ahr capacity, the charge current will have dropped to 30-40A within half an hour.

However as Eeyore points out, you will gain if using the inverter to draw a high current, but only when the inverter is supplying that high current.

Edited February 6, 2018 by dor
Change increase to decrease!!!

[canals are us?]

42 minutes ago, WotEver said:

The simplest way to parallel the alternators will be with a VSR - Voltage Sensitive Relay. 

About £35, or these folk will supply a kit with all the cables for a bit more:

https://www.12voltplanet.co.uk/voltage-sensitive-relay-12v-140a.html

Thanks for the link

Anyone have one of these? Looks a good bit of kit and even I could fit it and a cheap solution. Seems clever.

Would it enable both alternators to give charge? 120 amp should be fine as my alternators equate that under max conditions.

James.

Edited February 6, 2018 by canals are us?

[matty40s]

7 minutes ago, dor said:

A very significant point and one not realised by many people.  Just fitting a bigger alternator will not significantly DECREASE YOUR charging time.  This is because the charge current is controlled by the battery not the alternator. The only way to increase the charging current is to increase the charging voltage.

You can have a 100A alternator, but I bet, with 50% discharged batteries of 440Ahr capacity, the charge current will have dropped to 30-40A within half an hour.

However as Eeyore points out, you will gain if using the inverter to draw a high current, but only when the inverter is supplying that high current.

Fixed that for you 

[dor]

1 minute ago, matty40s said:

Fixed that for you 

Thanks for that.  you are of course correct (and honestly, it was what I meant to say).  I did say a few days ago my mind might be a bit wobbly for a while...

Original post edited.

[Tony Brooks]

59 minutes ago, canals are us? said:

Thanks for the link

Anyone have one of these? Looks a good bit of kit and even I could fit it and a cheap solution. Seems clever.

Would it enable both alternators to give charge? 120 amp should be fine as my alternators equate that under max conditions.

James.

I would have said the same as the other Tony (Wotever) and am about to fit one in place of a split charge relay on my boat although in my case its a single alternator boat. I am going to fit it so the solar will charge both banks when the domestic bank is well charged.

Paralleling the alternators will get you to maybe 80% of fully charge faster than with a single alternator but from then on you get little if any advantage. It will take a long time to get from 80% to near 100% charged with or without paralleling

I note that you make no mention of how you monitor your batteries, monitoring the state of charge will probably give longer battery life than a larger alternator. Spend £40 on a VSR and put the rest of the cost of a larger alternator towards an ammeter and Smartgauge.

[AndrewIC]

1 hour ago, canals are us? said:

Hi thanks for your reply. 90 amp would be better than 70!

I only have this photo. I can take any needed tomorrow when I clear the area ready to fit my inverter.

James

 

 

I have a BV1305, with the a single original Lucas A127 alternator (in the position at the top of your pic). The thing to watch if changing the alternator in tha position is length. There is very little room between the alternator studs and the dipstick tube on mine.

The Beta WOC (works) number should be on that sticker on the rocker cover. Mine had long since vanished, but Beta were able to trace it from the block serial number, which on mine is on the side of the engine underneath the exhaust manifold (and badly stamped, and full of paint!), almost impossible to see without sticking your head down the side of the engine with a very bright torch!

[WotEver]

5 minutes ago, AndrewIC said:

... on mine is on the side of the engine underneath the exhaust manifold (and badly stamped, and full of paint!), almost impossible to see without sticking your head down the side of the engine with a very bright torch!

... once it’s cooled down

 

[OldGoat]

UMM - a VSR isn't going to parallel the alternators is it? I thought it was to charge two batteries from one alternator??

To parallel two alternators you need high current diodes and sense wires - or am I out of date / missed a trick?

Be careful with higher output alternators on the from end of some Betas - it possible to get key chatter at slow engine revs which destroy the key and keyway. On some models you can get a kit to take the drive from the splines on the crankshaft - if they're not been sawn off (another reason for the WOC)

[WotEver]

2 minutes ago, OldGoat said:

UMM - a VSR isn't going to parallel the alternators is it? I thought it was to charge two batteries from one alternator??

Same difference. Think about it

3 minutes ago, OldGoat said:

To parallel two alternators you need high current diodes and sense wires - or am I out of date / missed a trick?

You most definitely don’t want to use diodes and drop half a volt. 

[GUMPY]

I've been using a VSR to parallel the alternators on my Beta 50 for years, seems to work a treat, however both alternators have to have the same  voltage from their  regulators or one will shut down early negating any benefit.

Edited February 6, 2018 by Loddon

[ditchcrawler]

5 minutes ago, Loddon said:

I've been using a VSR to parallel the alternators on my Beta 50 for years, seems to work a treat, however both alternators have to have the same  voltage from their  regulators or one will shut down early negating any benefit.

How about if you hit them with a big load so pulling both voltages down like running a washing machine

[Sir Nibble]

The main improvement from alternator paralleling is the improved charge at idle which is a way of improving the hours side of the A/h equation.

[nicknorman]

It’s interesting how people say what they were going to say, regardless of the question! The stated aim of the question was to provide sufficient power to run the washing machine from the alternators. And yet we have a bunch of replies telling us how bigger alternators won’t decrease battery charge time, and/or how to improve battery charge time!

A VSR will achieve the stated aim, fairly cheaply. It doesn’t matter about any difference between the alternators’ regulated charging voltage as with the very soft regulation, alternators only reach that limiting voltage at quite low currents. Worst case is some imbalance between the sharing of the charge current. Certainly with a high current demand to the inverter to feed a washing machine on heat cycle, it doesn’t matter at all.

[canals are us?]

1 hour ago, Loddon said:

I've been using a VSR to parallel the alternators on my Beta 50 for years, seems to work a treat, however both alternators have to have the same  voltage from their  regulators or one will shut down early negating any benefit.

Thanks everyone for your thoughts.

Is the regulator voltage written anywhere on the alternators? Is there another way to measure the starter battery and domestic banks voltage when engine running and see if the voltage is the same with a multimeter?

My charging as I'm marina based is an electroquest 30 amp battery charger that charges the 2 Trojan T105 and 110amp starter battery. Left on permanently to do it's thing. I only currently have a voltmeter plugged in the salon to see what's going on and never goes below 12.6 volts.

I have purchased a NASA BM2 battery monitor and also upgrading the PWM solar controller to a 40 amp MPPT one for my 380 watts of solar.

Also tomorrow installing a Victron multiplus 3kw inverter/charger. So taking out the old inverter and battery charger.

Most likely also buy 4x new batteries.

James

[canals are us?]

2 minutes ago, nicknorman said:

It’s interesting how people say what they were going to say, regardless of the question! The stated aim of the question was to provide sufficient power to run the washing machine from the alternators. And yet we have a bunch of replies telling us how bigger alternators won’t decrease battery charge time, and/or how to improve battery charge time!

A VSR will achieve the stated aim, fairly cheaply. It doesn’t matter about any difference between the alternators’ regulated charging voltage as with the very soft regulation, alternators only reach that limiting voltage at quite low currents. Worst case is some imbalance between the sharing of the charge current. Certainly with a high current demand to the inverter to feed a washing machine on heat cycle, it doesn’t matter at all.

Great, in a nutshell it'll work. Running the washing machine from the alternators and keeping up with the power demanded is all I want to create. Mostly marina based so mains battery charger can do the rest. Hoping to cruise from May for a month or two and run the washer. My washer has hot and cold fill.

I'll order a VSR tomorrow along with some 10mm cable for the new freezer wiring.

James

[nicknorman]

4 minutes ago, canals are us? said:

Thanks everyone for your thoughts.

Is the regulator voltage written anywhere on the alternators? Is there another way to measure the starter battery and domestic banks voltage when engine running and see if the voltage is the same with a multimeter?

My charging as I'm marina based is an electroquest 30 amp battery charger that charges the 2 Trojan T105 and 110amp starter battery. Left on permanently to do it's thing. I only currently have a voltmeter plugged in the salon to see what's going on and never goes below 12.6 volts.

I have purchased a NASA BM2 battery monitor and also upgrading the PWM solar controller to a 40 amp MPPT one for my 380 watts of solar.

Also tomorrow installing a Victron multiplus 3kw inverter/charger. So taking out the old inverter and battery charger.

Most likely also buy 4x new batteries.

James

It doesn’t matter about the alternator voltages.

I’ll just mention that with only 2 T105s you will struggle to get a lot of current out of them, not enough to get anything near 3kw. Of course I know that isn’t your intention, you intend to run heavy loads from the alternators. But I’m just mentioning that having 225AH of battery capacity doesn’t mean you can take 300A out (~3kw) even for a short time.