This is a Nasa BM1 Marine Battery monitor display (& Nasa BM2) and we’re fitting it to replace our our analogue battery monitor. After having battery problems on our trip to Belleek we decided to go ahead and fit a proper Nasa BM1 Battery monitor, there are other ones but in my opinion this one represents the best value for money.
It’s not too big a deal to fit it and I had the advantage of musing over the instructions for a week before I got down to the boat to install it. If you want to know how your batteries are behaving you would really benefit from this or a similar unit. The Nasa BM2 will take a higher amperage as is suitable if you have (or intend to install) a large inverter.
You may have difficulties getting the BM1 unit delivered to Ireland directly. If you use ParcelMotel.ie you should be able to get it delivered for the UK postage fee plus €3.95. ParcelMotel.ie almost always works out way cheaper that direct post to Ireland.
The Nasa BM2 is an identical unit with the single difference being that it can handle up to 200Amps while the BM 1 can only handle up to 100Amps. So if you have a hefty inverter onboard or if you are likely to install one in the future you may be better off using the Nasa BM2. The setup is exactly the same for both units.