Wiring ammeter to monitor solar output

[BozSail]

I'm installing a 100 watt solar panel and mppt controller on my sailboat. Is it useful to wire in an ammeter to monitor output? If so, how should it be wired?

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[Ex-Calif]

I would not buy a dedicated meter to measure 8 amps.

You should have something to monitor your batteries. Current two choices IMO are Smartauge and Victrom BMV602. Both are likely to exceed the cost of your solar install.

They do slightly different things and Smartgauge won't count amps.

You have a 37 foot boat and I expect you plan to expand power systems int the future.

I would get Smartgauge now and see if something better for amp counting comes on the market in the future. I think the BMV602 is fast reaching is "sell by date" from a technology standpoint.

[model 10]

Plus the shunt for the meter is a resistor. Who needs that?

[mbianka]

I have two Morningstar PWM 15 amp solar controllers. One charges the 12 volt house bank and the other the 48 volt propulsion bank. The 12 volt unit does not have the built in meter the 48 volt unit does. So I put an ammeter in line with the solar panel output for the 12 volt unit and it is helpful to monitor the amps flowing from the panel. When I get ambitious I will also use it to observe the shading effects on both the 12 volt and 48 volt panels due to the boom shadow. But, since things are working well as is it's not on the urgent side of the TODO list. IMO it's a good tool to have to check things out in the system(s).

[colemj]

What MPPT controller? Many of them count the amps/ahr/etc for you.

Mark

[Seawindii]

I installed an analog ammeter from Blue Sky that measures -100a to +100a. I have it wired to show net effect of all charge and all load currents -including alternator. It's an easy install and a I have found it to be a great tool when budgeting power usage or keeping an eye on charging currents. Really compliments the Balmar battery monitor.


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[GILow]

It my understanding that power lost to a good ammeter is negligible. Therefore I put an ammeter on the output of our controller as I find an analog meter so much better at quickly conveying how well the panels are running. The LCD display on our controller is too coarse in its graduations to clearly convey this information. Also a small panel meter is easy to place in a clearly visible spot. (With due regard to cable lengths and power loss)

Matt


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[Ex-Calif]

Originally Posted by Seawindii

I installed an analog ammeter from Blue Sky that measures -100a to +100a. I have it wired to show net effect of all charge and all load currents -including alternator. It's an easy install and a I have found it to be a great tool when budgeting power usage or keeping an eye on charging currents. Really compliments the Balmar battery monitor.


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Do you have a model number?

[MarkJ]

I bought a solar controller with digital ammeter in it because it was cheaper than a digital ammeter by itself!

Go figure!

[Jimbo485]

What was the cost of the panel in terms of $ per W?

How many extra Watts will the controller give you? What was the cost for this controller in terms of $ per extra Watt?

What can you conclude so far?

[noelex 77]

It is useful to know the output of your panels.

Many solar regulators will give you this information. Some battery monitors can also be fitted with a separate shunt to display this.
The battery monitors are great. They will give you lots of other information and will count AHrs which is often more meaningful than the instantaneous current.

A separate ammeter for the solar panels is easy to wire. You need a model that has a shunt. The shunt is installed in the wire from the solar panel. Two fine wires lead from the shunt to the ammeter which can be installed in a convent spot. It will also require a 12v supply. The hardest part is not the electrics but mounting the display neatly. Some units only have a shallow bezel which means the hole needs to be cut out carefully if you want to flush mount it. The bezel is usually designed for fixing in a thin metal or plastic panel and may not work in plywood.

[barnakiel]

If you like to measure things, get yourself a simple batt monitor that will add the amps together (and deduct whatever you use, if you wish).

We have an inexpensive TriMetric and I love to push its buttons to see how much we make, how much we consume and how much is left.

;-)
Have fun, make some sparks,
b.