WBjr regulating aux1

[heinburgh]

I'm posting this in both WBjr and Classic forums with the hope that the guys that know will spot this. I run a 5.4kW pv array with 2,200Ah battery bank. Every morning at around 10am (12pm in winter) the batteries are at around 95% SOC according to my WBjr, at which stage there is enough juice being turned away to run my 0.75kW irrigation pump that water a 2 acre piece of lawn. I'm having trouble setting up my aux relays to maximise irrigation time while making sure my batteries stay as healthy as they possibly can.

Currently I have one Classic set up to close aux1 when batteries reach 95% SOC. I have a second classic's aux1 set up with 'do not waste high', and I wired these two so that both relays have to be closed in order to switch on the pump. So when either of the two relays opens, the pump switches off. Switching on using SOC works great, it happens right when there is enough amps being wasted to run the pump, but switching off I just cannot get right.

Using the 'waste not high' feature works well except when the system is in float when it is meant to shut down the pump, for some reason the aux1 relay remains closed and the pump keeps on running even though there's not much sun left, draining the batteries. I have tried using WBjr SOC on its own by setting it at 99% on, 99% off (using local app) but having to wait until it reaches 99% SOC wastes a lot of solar power.

Any ideas on how I change the settings so that the classics switch off my pump as soon as the amps going into the battery bank becomes less than what they would normally need?

[boB]

What is your SOC% Aux 1  turn OFF setting ?  And does the SOC% come down to that turn-off % setting when that pump is on ?

It should turn off after the SOC% has dropped below the set point after the HOLD time timer has expired.

Unless there is something we haven't thought of, that question is kind of important.  Also, the WB Jr. has
to be connected to the Classic that you are using the SOC% On-Off of course.

boB

[heinburgh]

Hi Bob, sorry for my late reply.

I have the SOC turn off set at 89% and turn on at 94%. It doesn't allow a difference of less than 5% between the two. I do not actually use the turning off, since the sun has long set by the time my batteries reach 89%, and I do not want to run the water pump off my batteries at all anyway. Only excess solar power.

So switching on works fine at SOC 94%, and also switching off using the second unit's aux set on "waste not high" set at 0V. The issue only seems to be that when the classics go into float, it has a hard time switching off.

I'm having another issue with non-linear voltage readings on all my classics - the longer their cables to the battery bank the worse they are. I read another post where you gave instructions on adjusting the blue pot to try and get the readings as close to linear as possible, I'm going to give this a try tomorrow and see if it helps to switch off my aux waste not high when I have a more accurate voltage reading.

I'll post here what happens.