HELP: 12v water pump tripping enerdrive lithium bms

Hi Mick O
they said to charge the battery fully because it was brand new and it should be fine but it has not worked. the built in battery monitor system is cutting out as if the battery is flat but it comes back on, and then trips again as soon as the water pump is turned back on.

Thanks for the reply hkb

I have already tried wiring the pumps straight to the battery. Should i be wiring them through a relay?

Sounds like Enerdrive have fobbed you off, they know that unless the battery is pretty well dead flat there shouldn't be a problem. Hope that is not the case but doesn't sound good.

If the pumps trip the BMS when connected directly, by that I mean just connecting the pumps by a short jumpers and not the van wiring the issue is probably caused by electrical noise being generated by the pumps. This raises a couple of issues, first being the pumps should not be generating "interference" as there are regulations that manufacturers should be complying to. Secondly the battery BMS should have sufficient inbuilt suppression to noise to be able to function correctly for the intended purpose else it is not fit for purpose.

The battery I imagine is marketed as suitable for use in a caravan, it should therefore be able to handle items generally installed in a caravan. I also assume the pumps work ok when powered from another source, the 240V charger or AGM battery for example, if this is the case then I would be going back to Enerdrive and asking for a resolution. In the past though of have found they aren't the best company to deal with when things go pear shaped.

If you get no joy from Enerdrive then I would suggest you try passing the power wires to the pumps through using ferrite beads or a few turns around a toroidal doughnut and see if that helps. Other solutions could be a noise suppressor unit as used on car radios etc. That would be the easier solution perhaps, harder solution would be to try and get your money back from Enerdrive and by a system from Ev Power or another brands that works without hassles.

Thanks hkb
What kind of noise suppressor would you recommend? It’s so frustrating that you spend so much on “good gear” and only to have it let you down. Hopefully enerdrive can sort this for me but it’s looking like I’ll have to try the noise suppressor. Your reply has been very helpful!!

Cheers, Pat

Start with something like this from jaycar

https://www.jaycar.com.au/ferrite-bead-for-emi-suppression-pk-6/p/LF1250

If that doesn't work then you could try winding a few turns of the power wiring to the pump on
these

https://www.jaycar.com.au/l15-35x21x13mm-toroid-or-ring-cores-pk-2/p/LO1238

If real desperate one of these but make sure pump doesn't draw more than 10A

https://www.jaycar.com.au/10a-dc-noise-filter-improved/p/AA3074

Also make sure wiring to the pumps is good, no bad connections etc.

Hkb thank you so much mate those little filters have seemed to work.

Guys like you are bloody legends and thanks everyone else for the reply’s.
Hopefully it keeps working and I have trouble free power from now
????

No probs, good to hear the problem is hopefully solved.

Pat,

Enerdrive is a reputable organisation keen to improve their product.

I'm sure they would not be happy with something as simple and commonplace as a water pump screwing up their BMS on their lithium batteries.

I'm equally sure they would appreciate your telling them about your problem and how you resolved it.

Cheers

"Enerdrive is a reputable organization" Hmm

thanks a lot mate! got the pumps working for now. charged the battery to 100% and the system did a few funny things (turned on and off a few times) but its all sweet now. the battery sits at 13.4v now at 100%

thanks for all other replies also! much appreciated!

Hi lotty

After thinking the issue was resolved it seems to be back again.
Every time the pumps prime the whole system shuts down. The battery is saying it’s at 13.2v at 90%. Does this seem low? The battery is brand new and only been completely charged once. I’m thinking it might be a faulty battery but the smartphone app is telling me the health of the battery is perfect? Have you seen any issues like this?

Pat,

If you haven't already done so, I think it's time to talk to Enerdrive. Ask for Marius.

Warren
These pumps are 12v and made cheaply in China and most likely DO emmit some electrical noise into the supply line from the batteries. 240v ??????

Yes 240V AC. I think the spikes were the result of sparking in the relay as it reared its head after a couple of months. The worst offender was a large (by lab standards) furnace. With that at least we could schedule it to run after hours. The water pump was used to supply cooling water to the instrument it was resetting.