Ammeter for mains charger

[pcatterall]

There is no ammeter with the mains voltage 20 amp charger which came with the boat.
I would like to know what is going into the batteries and would like to install one.
This could be 'in line' on the lead from charger to battery.
Can I just buy a meter that is fitted in line or do I need one of these shunt things as well.
If the charger is left connected but off can there be feed back from battery to charger?

 

[mattnj]

if you are going to install a meter, it might as well be a meter to monitor everything, go for a NASA BM1, easy to install nice simple readout.

 

[Stu Jackson]

Depends on the amperage you're dealing with.

http://c34.org/bbs/index.php/topic,6032.0.html

 

[VicS]

Can I just buy a meter that is fitted in line or do I need one of these shunt things as well.

Your choice I think
If you are happy with a direct reading one to be positioned along the route of the wiring then that will fit the bill.
If you want to position the display at a remote location you will need one with a shunt.

If the charger is left connected but off can there be feed back from battery to charger?

That should be fine.

 

[Stu Jackson]

If you're going to the work of installing a shunt anyway, why not consider a battery monitor. Linked in the link in my previous post. The advantage would be that you'd see not only what's coming in but what's going out, too.

 

[elton]

I used to have a car charger permanently connected to my battery and wondered about drain back through it when disconnected from the mains. It wil vary according to the model, but I measured mine and it was less than 5 mA, so I left it connected.

 

[Heckler]

if you are going to install a meter, it might as well be a meter to monitor everything, go for a NASA BM1, easy to install nice simple readout.

+1
Stu

 

[NB Willawaw]

I normally use something like the Blue Seas digital ammeter with a 500A shunt which goes in the negative battery lead.

This will show charge and discharge current to/from the domestic battery bank and measures using the shunt.

Dead easy to install.

No the batteries shouldn't discharge through a marine charger when the charger is off.

There is no ammeter with the mains voltage 20 amp charger which came with the boat.
I would like to know what is going into the batteries and would like to install one.
This could be 'in line' on the lead from charger to battery.
Can I just buy a meter that is fitted in line or do I need one of these shunt things as well.
If the charger is left connected but off can there be feed back from battery to charger?

 

[pcatterall]

Many thanks guys. NASA BM1 on order!!

 

[VicS]

Many thanks guys. NASA BM1 on order!!

Take care to wire it exactly as shown in the instructions.

In particular there must be no connections to the domestic battery battery negative other than the shunt!

Diagram below may help.

Not shown on the diagram but BM1s now include the facility to measure the volts on the engine starter battery. There is an additional orange wire to connect for that purpose

 

[fergie_mac66]

There is no ammeter with the mains voltage 20 amp charger which came with the boat.
I would like to know what is going into the batteries and would like to install one.
This could be 'in line' on the lead from charger to battery.
Can I just buy a meter that is fitted in line or do I need one of these shunt things as well.
If the charger is left connected but off can there be feed back from battery to charger?

O to 30 amp meter here 10£

http://www.bardwells.co.uk/detail.a...id=PM01&manuid=&keywords=&minprice=&maxprice=