WOC Number and Alternator Paralleling.

[nicknorman]

2 minutes ago, canals are us? said:

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

Just make sure the VSR is rated to comfortably take the full output of the larger alternator.

If your washer has hot and cold fill, it shouldn’t need to bring the heater on and thus the power consumption will be quite small. Washing machines only use a lot of power during the wash when they are heating the water. The rinses, spins etc use very little.

[canals are us?]

41 minutes ago, nicknorman said:

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.

Ok great

I am planning on getting 4 new batteries as suspect the 3.5 year old Trojans are sulphated as never got an equalisation from my basic charger so planning to get 4 new ones, most likely ordinary cheapies due to the £560 cost, unless the 2 Trojans can be revived and just buy 2 new? Read mixing old and new is a bad idea? Voltage seems to drop quickly when off charger and drop below 12.6volts. Not looked after them the last 6 months unfortunately as low on de ionised water as 6mm below the top of the plates. Topped up now.  Hoping in the setup of the Victron can give a higher charge voltage which Trojans like. Thinking 4x110amp cheapies.

James

 

Edited February 6, 2018 by canals are us?

[Tony Brooks]

12 hours 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.

Para 1.

True but I suspect the OP has been looking at the Sterling A to B at the price he quotes and although it will in effect parallel his alternators it can not even make them, produce any more amps than they were designed to do. Add to that the fact that it looks like  single V belt alternator drives so he is limited to how much higher output alternators he can fit without risking running into belt problems. If he can get hold of the Bosch alternator sold as a high output A127 (as per Acorn catalogue of a few years ago) it will probably work but even then its only a 90 amp machine. That gives him an extra 240 watts if he can get it on in place of the domestic alternator or 480 watts in the case of the engine alternator. If he changes both that 720 watts extra. giving 2400 watts in total, but at what cost and is 2400 watts enough to cover the said washing machine load? If he leaves the heater connected and uses it I suspect not so. As others have suggested, in my view, the cost effective way is to fill via a thermostatic mixing valve and set the control to a cold wash. I acknowledge he will be rinsing using some water from the calorifier but that's not normally a problem when cruising.

Para 2

Totally agree

[Eeyore]

2 hours ago, Tony Brooks said:

Para 1.

True but I suspect the OP has been looking at the Sterling A to B at the price he quotes and although it will in effect parallel his alternators it can not even make them, produce any more amps than they were designed to do. Add to that the fact that it looks like  single V belt alternator drives so he is limited to how much higher output alternators he can fit without risking running into belt problems. If he can get hold of the Bosch alternator sold as a high output A127 (as per Acorn catalogue of a few years ago) it will probably work but even then its only a 90 amp machine. That gives him an extra 240 watts if he can get it on in place of the domestic alternator or 480 watts in the case of the engine alternator. If he changes both that 720 watts extra. giving 2400 watts in total, but at what cost and is 2400 watts enough to cover the said washing machine load? If he leaves the heater connected and uses it I suspect not so. As others have suggested, in my view, the cost effective way is to fill via a thermostatic mixing valve and set the control to a cold wash. I acknowledge he will be rinsing using some water from the calorifier but that's not normally a problem when cruising.

Para 2

Totally agree

I was thinking of this one http://www.prestolite.com/pgs_products/specs.php?item_detail_id=32897&item=66021590M&product=Alternator as found on the later Isuzu marine engines as a direct replacement for the existing A127 type.

AndrewIC mentioned having a A127, and being very close to the manifold when mounted in the "upper" position. I would take the small 50 amp (Nippon Denso?) along to my nearest repairers and ask if they have a 70 amp in a similar case and mounting type. They will have one, but I can't remember what I got last time I did this!

As Tony says these are the largest you can reliably drive with a single V (wedge) belt, as a rough guide 70 amp where the belt goes around 3 pulleys and 90 amp where it goes around 2 pulleys. Its all about the arc of contact between belt and pulley; use a premium brand belt and keep it well aligned, correctly tensioned and oil free.

I acknowledge that some of my earlier comments were not directly related to the OPs question. However this forum regularly receives queries regarding this as a solution to charging woes; just wanted other readers to see that this is a similar solution to a different problem. Yes, could have been worded better in my earlier posts 

 

Edited February 7, 2018 by Eeyore

[notts_alan]

Would the sterling alternator to battery chargers be any good ? You can connect both alternators to it and have outputs to starter battery and domestic bank , it boosts the domestic bank channel .

Maybe worth a read up on their website.

[WotEver]

11 minutes ago, notts_alan said:

Would the sterling alternator to battery chargers be any good ? You can connect both alternators to it and have outputs to starter battery and domestic bank , it boosts the domestic bank channel .

Maybe worth a read up on their website.

Why pay well over £200 when he can do it perfectly for £35?

[nicknorman]

15 minutes ago, notts_alan said:

Would the sterling alternator to battery chargers be any good ? You can connect both alternators to it and have outputs to starter battery and domestic bank , it boosts the domestic bank channel .

Maybe worth a read up on their website.

Not for the stated aim. The purpose of the fairly expensive A2B is to increase the charging voltage and give it a sharper regulation so that the regulated charging voltage is achieved at a higher current, so as to minimise battery charging time. But the stated aim is to power the inverter, and an A2B will give no added power from a heavily-loaded alternator

[Dr Bob]

2 hours ago, nicknorman said:

Not for the stated aim. The purpose of the fairly expensive A2B is to increase the charging voltage and give it a sharper regulation so that the regulated charging voltage is achieved at a higher current, so as to minimise battery charging time. But the stated aim is to power the inverter, and an A2B will give no added power from a heavily-loaded alternator

Agreed. I recently fitted the sterling AtoB and it is a great bit of kit......and expensive....but I got it for my Beta 43 as the alternators were only putting out 13.9V max on absorption. The AtoB takes it up to 14.7V. That is not the OPs problem.

[Sir Nibble]

On my phone its a major performance using this site but looking at the picture I don't know if it's relevant to the discussion but that engine doesn't have an A127 fitted. There is a nippon denso and what looks like a valeo marine unit.

[David Mack]

19 minutes ago, Sir Nibble said:

On my phone its a major performance using this site but looking at the picture I don't know if it's relevant to the discussion but that engine doesn't have an A127 fitted. There is a nippon denso and what looks like a valeo marine unit.

And the alternator at the top of the picture appears to have no fan, so would get hot if you push the power demand.

[nicknorman]

12 minutes ago, David Mack said:

And the alternator at the top of the picture appears to have no fan, so would get hot if you push the power demand.

Surely it has an internal fan? Built into the rotor, like this:

http://www.kava-auto.com/product/533-nippondenso-alternator-parts-nippondenso-70-100a-alternators-rotor-1-1029-01nd--7417/

Edited February 8, 2018 by nicknorman

[Eeyore]

1 hour ago, Sir Nibble said:

On my phone its a major performance using this site but looking at the picture I don't know if it's relevant to the discussion but that engine doesn't have an A127 fitted. There is a nippon denso and what looks like a valeo marine unit.

Opps, I’d best get back to Specsaver’s.

[Sir Nibble]

1 hour ago, nicknorman said:

Surely it has an internal fan? Built into the rotor, like this:

http://www.kava-auto.com/product/533-nippondenso-alternator-parts-nippondenso-70-100a-alternators-rotor-1-1029-01nd--7417/

One at each end