STECA solar regulator

Hi Bill, have used one in our KK when we had it and it needs to be connected to the battery every time before the panels. The circuitry requires the battery to fire up, then when the panels are connected, it works well.

I liked the one in the KK enough to have one on the solar system for the electric fence here. It is also a power controller, so if charging fails, it needn't actually wreck your battery, it will protect it.

I like the fact it has a LED read out to tell me the battery and charge capability. Great inexpensive little solar charger.

Oh, yes, leave it connected while the 240v charger is going

It does not matter what sort of controller you have you can connect another charger across it. It does not matter whether it's another solar charger, mains powered one or a DC-DC charger. The only thing you have to watch is that when they are all likely to operate together you are not supplying too much charge current to the battery.

When you have several chargers connected to a battery they will all have slightly different absorption set voltages. Whilst the battery is well discharged all the chargers will supply a charge current up to their maximum capacity. As the battery terminal voltage rises to nearly the absorption voltage setting the battery will start to reduce the amount of current that it will accept. The output current of the chargers will reduce as a consequence. The charger with the highest voltage set point will supply the majority of the current. The ones with the lower voltage set points will cease supplying lots of current and will go into their float charge stage. When the charger with the highest voltage completes the absorption charging, it will then switch to float voltage. Nothing will be damaged during this progress. If you don't understand the terms I used then go to this link.

The biggest problem you will have with your Steca controller is that it was designed for the communications industry and they use positive earth systems. This means that the positive terminals on the controller are all connected together and the negative terminals all work independently. If your battery is also charged from the vehicle alternator then the negative terminal of the battery will be earthed. You will be able to connect your mains powered battery charger across it. For the controller to work properly you will not be able to earth the negative sides of the solar panel connection lead or the load system. If you have something that you are powering from your battery that is metallic and the case is connected to the negative line (like a car radio) then make sure that it does not touch the metallic parts of your vehicle. If this happens you will short out the output current metering of the controller and this will effect your SOC readings.

Roachie,

When I was setting up our slide-on camper, I procrastinated long and hard about what solar/240v charger system to fit. Wanted MPPT solar, 240v charger(Ctek 25 amp), LED battery monitor and smart charger off the alternator. When you add the cost of these, using quality items, they add up to almost the same cost as a Redarc BMS system. Bit pricey, but got one cheaper from Kulkynne Kampers, at just over a grand. Charging rate is a bit light at only 15 amps max, but a new model(with a new price!) is rated at 30 amps max.

We haven't done a great deal with the camper, in remote areas, but it all works well. Have a 160w panel mounted on the roof, and plan to add a couple more panels, when/if, we ever get away on our bucket trip. The fact that Mick O had the same unit, and he had desert tested it was a bit of a carrot for me too.

The third thing that helped me decide was the fact that the BMS doesn't need an "ign" sensing wire run into the unit, to switch between alternator or solar charging. The BMS meets the KISS principles. :-)

Bob