Multiple Battery Backups, Multiple Pumps, One Wire

[static416]

Hey, I have a configuration at the moment with two Icecap Batteries, running to a single WaveEngine LE.

This is a defined configuration in the Hydros docs, and shown here



However, I'm add a second WaveEngine LE, and rather than run a second wire through the wall, I was thinking of:
1. Connecting the second WaveEngine power supply to the open port on the second battery.
2. Forking the single wire that leads to the existing WaveEngine, and connect a second

Would this work and not explode or damage anything?

 

[Danny]

Why not put a battery on each. You would need a cable kit to do that.

 

[static416]

Why not put a battery on each. You would need a cable kit to do that

Batteries are in another room and I'm trying to avoid running a second cable through the wall. So trying to find a way to reuse the one I already have installed.

 

[Danny]

Batteries are in another room and I'm trying to avoid running a second cable through the wall. So trying to find a way to reuse the one I already have installed.

In answer to your original question I have not tried to run two WE's with the same supply so I don't know if it would work or not. Combining your supplies and batteries will basically make the supply the same one. Also there may be repercussions hooking both AC supplies up together since the supplies may not have any isolation. I think the isolation is within each WE and not the supply itself.

 

[static416]

Yeah, this is what I gathered from research online. It seems likely that I'd have essentially treat the two battery backup configurations in the same way that you'd join two power supplies in parallel to double the current. I'd have to wire in a rectifier to prevent issues.

Not sure that I care quite enough to do that.

 

[JeffB418]

technically you can run a single battery on a fill WE, and 2 WE LE is effectively the same thing as a full WE with maybe alittle more overhead because of 2 processors vs 1 but I don’t think that’s an issue. I’d have to check what my full WE power supply’s current handling is, but if you run a single power supply into the 2 batteries that’s big enough for 2 WELE then you should be able to just split the power after the batteries to each WELE. I THINK that the WELE supplies are smaller than a full WE but I am not sure. What is the max output current on each supply you have? I can check my WE power supply tomorrow and we can compare. I believe they may have shipped the larger WE power supplies with the WELE at some point due to availability so yours may be big enough but not sure.

If not you can always buy the larger WE supply here and use that and split power after the battery and be good. WaveEngine/WaveEngine LE Power Supply

 

[static416]

technically you can run a single battery on a fill WE, and 2 WE LE is effectively the same thing as a full WE with maybe alittle more overhead because of 2 processors vs 1 but I don’t think that’s an issue.

If not you can always buy the larger WE supply here and use that and split power after the battery and be good. WaveEngine/WaveEngine LE Power Supply

Spliting the output isn't dangerous AFAIK, it's just doubling the input that's an issue.

Buying a WE powersupply and then using that to power both is a great idea.

One less wire in my cabinet!

The Kraken can't come soon enough.

 

[static416]

If not you can always buy the larger WE supply here and use that and split power after the battery and be good. WaveEngine/WaveEngine LE Power Supply

So looks like the larger PSU is 6.5A vs the 3.5A for the WE LE. It's probably ok to just use a single 6.5A for both I imagine?

The primary power draw on this is not the WE units themselves, but the pumps they are connected to, and must be sized for the largest officially supported pumps.

In my case, one of the WE LEs is driving two Octo 2's, instead of the Octo 4's it's capable of. So I likely have some headroom.

 

[Redemptioner]

You just need to run the batteries in series as the batteries have pass through on the pump power input. So plug your 2 battery chargers in, then plug the smaller battery into the larger one (via pump out into pump in), then plug the pump into the larger battery. Good to go.

If you run it the way you have it in the picture at the start, you risk a burnout dure to current inrush between the batteries when they are at different states of charge. You can however put a couple higher current diodes inline from each battery pump output if you want to run them in parallel as you have picture.

 

[static416]

If you run it the way you have it in the picture at the start, you risk a burnout dure to current inrush between the batteries when they are at different states of charge. You can however put a couple higher current diodes inline from each battery pump output if you want to run them in parallel as you have picture.

So that photo is the officially recommended configuration within the manual. So I have to think they already have diodes within the Icecap battery units.

Otherwise yes, bad stuff could happen.

 

[Redemptioner]

So that photo is the officially recommended configuration within the manual. So I have to think they already have diodes within the Icecap battery units.

Otherwise yes, bad stuff could happen.

Well if they know what they are doing they should just have used a 30A bridge rectifier (bunch of diodes in a loop) in there for the switching, if they did it is fine to connect as per diagram, but it seems most companies making these backup devices have no idea what they are doing (same goes for many other electronics). You can check easily by looking at the output voltage drop between the pump-in port to the pump-out port, if it drops around 0.7 volts then you can parallel, if not you should avoid following the brands suggestions.....

On a side note, you can also add multiple power supplies to a Hydros controller using a diode (or a battery) inline on the power supply to add power redundancy to your collective (the diodes will in most cases fit in the connector as you generally only need low current one's due to the poor/low current rating on hydros controllers). Admittedly CV could just uses some slightly better power supplies that already have the diode onboard, or maybe add the additional diode to the terminated version next to the resistor they are already adding....