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Member Since 04 Apr 2011
Offline Last Active Today, 05:11 PM

Posts I've Made

In Topic: Preventing damage to alternator if ignition on without engine running..phew!

Today, 01:16 PM

Thanks for the replies...
Indeed, an 'Alpha Pro' is Mastervolts offering of an Adverc, Stirling etc. It phases the amount of amps as well as monitoring the temperature of the batteries via sensors to ensure that batteries are fully charged and not just partially as in a car etc.
It's a complex but professional system with a 160ah Leece Neville alternator that charges the domestic bank (4 x 200ah gels) at 12v and the starters (2 x 110ah traction) at 24v via a Mastervolt DC-DC converter.
The previous owner as mentioned had to replace the alternator when the ignition had been left on beyond it's 'beep' beep' which occurs at 90-120 secs. SO I thought one of our electrical geniuses may have a solution which would in essence, switch the power off to the ignition. Very occasionally, the 1.7 ton Kelvin K3 stalls if the revs are reduced to a minimum in a hurry when in one of those 'oh shit' situations and to get down to the engine room in a hurry (or remembering to in such a situation) is not always practical.

One of my alternators referred to above is the same make/output as yours and as mentioned I didn't have an issue. I can't comment on the Mastervolt device though, but it can't put more current through the stationary alternators field than would happen without it fitted.

Incidentally isn't the beep there to tell you you have left ignition on. Guess it may not be loud enough though.

In Topic: Preventing damage to alternator if ignition on without engine running..phew!

Today, 12:37 PM

The Alpha Pro appears to be a Mastervolt offering. From what I can see it piggy backs an alternators internal regulator to provide user selectable multi-stage charge regulation, much as the Sterling and Adverc devices. A DAR in other words.

I doubt if any great harm will come from leaving the ignition switch on accidentally, other than flattening battery of course. I admit to doing this accidentally myself for an hour or so without issue to either DAR controlled alternator.

In Topic: Alternator question for Sir Nibbs please

Today, 09:15 AM

Alternators seem quite happy running without load. The problem arises with the sudden removal of load. I have to say that I have never seen the sudden alternator demolition which we are told is the inevitable result of disconnecting the battery except with early battery sensed machines. it should be remembered that for the alternator in it's natural habitat on a vehicle the battery is a small proportion of the load.

There's a huge difference between disconnecting the battery (with other loads still present) and disconnecting the alternators output though.

ETA: Whoops! I think Nick said the same thing earlier.

In Topic: Living with Oil Filled Rad

Yesterday, 01:00 PM

Just bought a 500 watt oil filled radiator to leave on boat for background heat. On testing at home I was pleased to see that it appears to have two thermostat's in series. The one controlled by a temperature select dial allows you to hear the point it clicks in/out. Initially thought there was a fault though since it shut off well before it reached the off point when set to near maximum. After three or four minutes it cut back in though suggesting there is a second fixed upper temperature cut-out.

End result is that for any setting much above mid range on the dial it seems to spend as much or more time off than on. An added safety bonus is the 3 amp fuse in the plug. Must be drawing close to that when on.

In Topic: Alternator question for Sir Nibbs please

Yesterday, 12:43 PM

Thanks, that is rather what I thought. I therefore don't understand why the likes of Beta go to the trouble of running a wire from the domestic alternator B+, up to the panel, via a relay in the panel and warning light, and back down to the D+ terminal, when they could have just run a single wire from the ignition switch via the light to the D+. Any thoughts on why they might do this, other than to avoid the possibility of a slightly glowing light when the battery SoC is very mismatched?

I think you have just answered that last one yourself Nick. They wanted to be seen adopting good practice and not taking short cuts, even though only a possibilty of a warning light issue.

You may note I was on the point of adopting a relay myself until Gibbo's comments suggested the shared ignition feed wasn't the cause of my issue anyway.