Controller Load?

Brianinsocal

Is the load on the controller that can be used to run items equal to the amps of the controller? I read where you use the load to run some items and it will keep the battery from discharging to much. Not sure if I read that right.

Thanks,
Brian

Cariboocoot

Re: Controller Load?

That's what they are for: low current DC loads that you need to have shut off before the Voltage drops too much. Some have programmable LVD, some have a couple of choices for set levels, some have one fixed point of disconnect.

westbranch

Re: Controller Load?

most of the CCs with a "Load" connection have timers built in and were intended to run a light or 2. Mine has 8 different time combinations that are pre set and you pick one...

Cariboocoot

Re: Controller Load?

westbranch wrote: »

most of the CCs with a "Load" connection have timers built in and were intended to run a light or 2. Mine has 8 different time combinations that are pre set and you pick one...

Sounds like a SunSaver with lighting control.

basewindow

Re: Controller Load?

Generally the load Amps are the same as the rated Amps for the controller.
Mine is a 30A controller and the rating for the load side is also 30A.
However I have seen some with different ratings. 30A controller but only 20A load. Be best to check the controller documentation.

Kentill

Re: Controller Load?

Would it be better to connect a inverter (12 v in 120 volt out) to the load connection or the battery? If you connect the inverter to the battery you could run the battery down to 10 volts before the inverter shuts off. If you connect to the load connection you could shut off the inverter before you run the battery down to 10 v. Is that correct?

Kent

Cariboocoot

Re: Controller Load?

Kentill wrote: »

Would it be better to connect a inverter (12 v in 120 volt out) to the load connection or the battery? If you connect the inverter to the battery you could run the battery down to 10 volts before the inverter shuts off. If you connect to the load connection you could shut off the inverter before you run the battery down to 10 v. Is that correct?

Kent

What inverter?
Usually an inverter draws more current than is available from the LOAD terminals on a charge controller. For example the 30 Amps given in this thread would be 360 Watts. In other words it might handle a Morningstar 300 Watt 12 Volt inverter, but certainly nothing larger.

Better inverters have programmable LVD. For the ones that don't you can either rig a Voltage-controlled switch to shut it off before the batteries go below your preferred minimum or take your chances. If you've sized things correctly the problem doesn't arise.

But as a rule you don't connect an inverter to a charge controller's LOAD terminals.

Kentill

Re: Controller Load?

I see you point thank you. I'm just trying to figure what you can hook up to the load connection. I guess I'm trying to figure what I could connect to the load terminals to use the excess power generated when the batteries are charged up.

BB.

Re: Controller Load?

Some charge controllers you can program the Load Terminals for lighting (i.e, 2-4-6-8 hours of landscape lighting after sunset).

Generally, AC inverters have protection built in for over/under DC voltage and if you connect a large inverter to the load output of a typical charge controller, you will pop fuses or possibly even fry the charge controller.

If you have other "small loads" (HAM radio, some lighting, etc.), you can program the controller to turn off at ~11.5 to 12.0 volts on the battery bank. It can help reduce the chances of killing a battery bank (or killing a DC pump motor/radio electronics)--But in general, monitoring battery bank voltage is not very accurate for estimating state of charge.

-Bill

Cariboocoot

Re: Controller Load?

Kentill wrote: »

I see you point thank you. I'm just trying to figure what you can hook up to the load connection. I guess I'm trying to figure what I could connect to the load terminals to use the excess power generated when the batteries are charged up.

Actually the LOAD terminals won't do that; they supply power anytime the Voltage is above the on/off threshold. To control things based on SOC or at least charge stage you need a more sophisticated charge controller. That would be from simple 'stage switching' up to the MidNite Classic's "Waste Not" function which can meter out the power according to how much is available from the array yet not being used. It gets pretty complex at that level.

Kentill

Re: Controller Load?

So if you are going to use the load terminals you probably would not be using the battery bank for anything else?

Cariboocoot

Re: Controller Load?

Kentill wrote: »

So if you are going to use the load terminals you probably would not be using the battery bank for anything else?

That isn't a problem. You could have DC lighting on the LOAD terminals and an inverter connected directly to the battery, for example.

basewindow

Re: Controller Load?

Kentill,

For example

I have a small system.

I run my LED lights and DC water pump from the LOAD side of my controller. It's rated to 30A but having said that I don't think I'd be to confident running 30A through it for long. Luckily about 14A is the max it would ever likey to get, and that's with everything on at once. (Never happens)

I run a 600/1200W Inverter (Connected directly to the battery) the for small AC loads (though it's actually way oversized for anything i use it for, I will probably replace it with a 300W when the time comes).

For larger AC loads such as vacuum, coffee maker, tools, I use my Genny.

Hope that helps.