Water Pump affects kitchen sink light

Parlando

When we turn on water for the sink, and utilizing the pump, and have the over sink light on, the light flickers the entire time the water pump is working.  Is that normal?

Grumpy_G

Not uncommon at least. The pump has a pressure switch and typically the pump recovers pressure faster than the water use requires so you get that characteristic da-da-da-da noise when the pump turns on and off in rapid succession. It's more noticeable with a partially discharged battery. 

manyman297

So we had the same issue. Everybody gets the initial flicker when their pumps turns on but ours was flickering the entire time the pump ran. Also, some lights would flicker (just barely) when the fridge was running.

What I surmised is that our batteries might be failing (further testing needs to be done) as they are losing their charge much faster than normal. Once the battery gets to around 65% we notice the flickering (because the voltage is low). 

Somebody on here pointed out that another benefit of lithium is that you don’t get the drastic falloff in voltage as the capacity decreases like you do with AGMs (which explains the flickering).

So there’s a good chance we’ll upgrade next spring to lithium 

qhumberd

In our 400 we get a flicker when our water pump runs and the battery switch is off and connected to shore power, so my thought is that it has something to do with the converter. Our electrical experts may be able to explain.

manyman297

@qhumberd Is it a sustained flicker or just a brief flicker as the pump turns on? 

qhumberd

In ours the lights flicker when the pump runs in intermittent fashion, and seems to happen when the pump activates. We don’t see it when the pump is running continuously. Again, this is on shore power with battery switch off.

manyman297

@qhumberd I see. That seems less troublesome (not sure ours does the smae) since it is a larger initial power draw even on shore power. Ours constantly flickers once the voltage reached a certain point but that’s typical…but it also means our batteries aren’t holding a charge as well.

Parlando

My experience has been using battery power, not plugged in.  It flickers constantly while the pump and the light are engaged.  Thanks for everyone's replies.

Maxcamp

Yes, disturbing strobe effect from sink light while pump runs on battery power.  Not noticed on shore power.  Might examine the lighting specs. 

  I imagine the circuit board characteristics of LED lights varies by manufacturer, and running pump momentarily draws light circuit voltage down to a minimum required threshold.   Wonder if upsizing lighting wire gauge would help, but more trouble than worth to me.  Some meter testing would clarify issue.

Example:
After substituting the original  nucamp overhead puck lights, i wired the 12v originals in my pickup truck cap.  In testing  they worked fine off truck battery.... but not off my wired cap circuit.  Testing elicited voltage distance drop to just below a 11.2 to 11.4 volt minimum threshold for these lights.  At a resting truck battery voltage of 10.8v these puck lights refuse to fire up.