which battery monitor

[ianj99]

The BM1 only does one bank and is easy to wire in. Seems to work OK with two modes. Not sure of the value of monitoring the engine start battery as this does little work and I can parallel the house bank if necessary for an emergency start.

I fitted a 3position 4pole switch to my BM1 and with 4 shunts, can use it for 3batteries and the alternator.
The AH remaining feature isn't useable, but I prefer to use battery volts as an indication of battery state.

 

[noelex]

Most have been mentioned, but here are couple of others

Blue seas vsm 422: Gives lots of data will measure AC and tank volume as well.

Sterling power monitor: will measure 3 shunts ( from memory)

mastervolt view easy: Very expensive but will team with inverters etc for a larger boat

Link : . Lots of models, but tend to be expensive in the UK

Outback mate and dc: Expensive but will team up with the outback solar regulators, giving some great features for boats with large solar arrays

Trimetric: very good

Unless you are very electrically challenged I would get a " proper" battery monotor rather than the smartgauge.
The NASA units are hard to beat at the price for small boats.

 

[Amulet]

I've got two Nasa BMs, one for each battery bank.........a bit OTT some might say but they are bloomin marvelous......and if I was refitting again I'd do the same.

ps, my boat has two battery banks and they can both be used for domestic or engine., they are not dedicated to either.

I have two too to monitor two symmetrical banks and like the arrangement fine. Engine is small and easily started with a general purpose battery.

 

[cimo]

what is the best battery monitor to get for a 2 x 12v battery system (one start one domestic)

By best I mean economic as well Is that NASA BM thingy any good?

to address the economic aspect, you could consider the following shunted solutions to complement your existing volts panel gauge & battery selector switch (I'm assumming you have these already)?

http://www.ebay.co.uk/itm/Mini-Blue..._Measurement_Equipment_ET&hash=item2313e685f6

use two of above, one to measure alternator o/p and one to measure current draw, or alternatively the gauge below will give you net current flow. Combined with the volts gauge & slector switch, you'll have everything you need to monitor battery status. (offered simply as an alternative - I love the look of analog gauges).

http://www.ebay.co.uk/itm/Round-Ana..._Measurement_Equipment_ET&hash=item2562f23f6e

 

[PabloPicasso]

We have the BEP Marina battery monitor DCM600.
It is significantly more expensive than the NASA.

Ok more expensive but is it better? Or have you wasted the difference in dosh?

 

[PabloPicasso]

Couldn't help imagining Harry Enfield's Brummie accent there.

yes not a helpful post

 

[PabloPicasso]

So a BM-1 is the better option judging by the posts here. But first I must get the biggest battery I can afford and find space for

 

[Richard10002]

So a BM-1 is the better option judging by the posts here. But first I must get the biggest battery I can afford and find space for

Don't forget the BM-2 for £119

 

[PabloPicasso]

now why would I need a BM 2?

 

[pvb]

now why would I need a BM 2?

You wouldn't. It's like the BM-1, but has a 200A shunt instead of a 100A shunt. With only one battery, you won't need the larger shunt.

 

[PabloPicasso]

Ok how do you work out what size shunt is needed? Is it dependent on max amps likely to be drawn or on the ah rating of the battery or batteries

 

[Tintin]

Ok how do you work out what size shunt is needed? Is it dependent on max amps likely to be drawn or on the ah rating of the battery or batteries

The Nasa comes with a shunt - no need to worry about it.

 

[pvb]

Ok how do you work out what size shunt is needed? Is it dependent on max amps likely to be drawn or on the ah rating of the battery or batteries

Max amps. With only one battery, you're unlikely to be drawing more than 100A.

 

[noelex]

Ok how do you work out what size shunt is needed? Is it dependent on max amps likely to be drawn or on the ah rating of the battery or batteries

Maximum amps drawn or put in.

 

[pvb]

The Nasa comes with a shunt - no need to worry about it.

Try to keep up! There are 2 versions of the Nasa monitor; one with 100A shunt, one with 200A shunt.

 

[Tintin]

Try to keep up! There are 2 versions of the Nasa monitor; one with 100A shunt, one with 200A shunt.

Good god man. Have they added a new product?

 

[VicS]

Try to keep up! There are 2 versions of the Nasa monitor; one with 100A shunt, one with 200A shunt.

Actualy there are four versions
There is the BM1 Compact which comes in darkgrey or white. A few less bells and whistles IIRC

 

[pvb]

Actualy there are four versions
There is the BM1 Compact which comes in darkgrey or white. A few less bells and whistles IIRC

Yes, there's also the compact version, listed in the "Caravan Products" section of Nasa's website for some strange reason.

 

[pvb]

Good god man. Have they added a new product?

You know what Nasa are like - cutting edge of technology...

 

[Richard10002]

now why would I need a BM 2?

If you have an inverter that might draw more than 100A, you might need a 200A shunt.

Ditto if you have an alternator and/or battery charger that charges at more than 100A.

I understand that, if you have a BM 1 , and draw/charge at more than 100A, the unit will record its, but won't display more than 100A as the current current being drawn or put in.