- Jan 13, 2020
- Funster No
- Hymer B514
- 6 months in a 10m Southwind in the USA (2014). Just bought a Hymer and embarking on a tour of Spain
Thanks, really helpful. It looks like I need 100/50 with the set up I’m planningThe idea is not to exceed the voltage and current limits. For a 100/50 regulator, 100 is the voltage input from the panels, and 50 is the current (amps) output to the batteries.
If the panels are in parallel - as usual on motorhomes - the voltage will be the same as a single panel voltage of 20 to 40V, so voltage is never a problem.
To work out the current, take the nominal panel watts and divide by the BATTERY voltage, then take about 70 or 80% of this if in Europe with the panel flat on the roof.
Example: three 120W panels: 360/12 = 30 amps, 80% of that is 24 amps. So if the choice is a 100/20 and a 100/30, it would have to be the 100/30.
Don't be misled by the 'max power current = 5.45A'. That's the PANEL output current, at the max power voltage of 22.0V. When the regulator steps down the voltage to feed the battery, it steps up the current to keep the power (volts x amps) the same.
So a 100/30 regulator can manage about 400W of panel if feeding a 12V battery, but can manage 4 x 400 = 1600W of panel if feeding a 48V battery. That's one reason for using higher battery voltage on a house installation, where the only thing connected to the battery output is the inverter.
I am waiting for a call back from them, thanks (although I am in Spain)Look at ultramax 480 quid for 100ah, bms inside. What’s not to like? You can have as many as you like in paralel. They based in London, UK vat invoice, ebay shop free delivery mainland uk. Still expensive? I don’t think so.
A fuse is a safety device. Any wire connected to a battery needs to have a fuse. If no fuse is wired in, then if the metal part of the wire touches the metalwork the battery is shorted, and the wire heats up until it is glowing red-hot and can easily start a fire. To avoid that, a fuse is wired in so that if the wire touches the metalwork, the fuse blows instead, and cuts off the battery current.Can anyone tell me what function this fuse serves in the solar set up?
Thanks... though I know what a fuse does... the question was intended to be - in which part of the circuit does this fuse sit.A fuse is a safety device. Any wire connected to a battery needs to have a fuse. If no fuse is wired in, then if the metal part of the wire touches the metalwork the battery is shorted, and the wire heats up until it is glowing red-hot and can easily start a fire. To avoid that, a fuse is wired in so that if the wire touches the metalwork, the fuse blows instead, and cuts off the battery current.
In your solar circuits, it depends on whether the fuse is between the solar controller and the battery, or between the solar controller and the panels.
On the battery side it is an essential safety device. On the panel side it is not really necessary because shorting the solar panels does not lead to excessive current like when you short a battery. But sometimes they are fitted anyway, and can be handy if for some reason you want to disconnect the panels from the controller.
You could try just replacing the fuse to see if the battery starts charging. If the new fuse blows there might be a wiring fault.
If the fuse has blown it's almost certainly in the part between the controller output and the battery.Thanks... though I know what a fuse does... the question was intended to be - in which part of the circuit does this fuse sit.
Agree, we got 150w solar, plenty of powerI have to say totally confused by all this power people seem to be using I mainly FLT and I have 120w panel which is getting old now and two 110 amp LA's and 85amp vehicle batt I use lap top phones and TV all charged off of leisure system LED lighting and camp here as well as abroad late and early in the season and never once has my system dropped below good ( my system reads very good, good, low, then red light comes on) never seen the other two am I very low usage which I doubt or our people just over worried about power and Hording it