My apologies if this question has been asked before or is too basic. I couldn’t find something relevant through search, although I found some related posts.
I have a Quattro 10k which shares one neutral between AC Out 1 and AC Out 2. Because I’m dealing with high currents (about 120A with pass through), my plan is to double up on 16mm sq. on the line terminals of AC Out 1 and AC Out 2 (one wire is enough for AC out 2 but I like things to be symmetrical and nice). My challenge is what to do with the neutral terminal since I can’t stack 4 lugs on that neutral. Is it fine if I run just 2 wires of 16mm sq. from the neutral terminal to a busbar (I can also use terminal distribution blocks instead but the theory is the same) and run appropriately sized neutrals to my loads from there?
What type of Quattro exactly? The ones that have 100A transfer relays use M6 bolts for the AC connections, while the 50A transfer ones use cage clamps, my guess is you’re asking about the cage clamp model. Pulling 120A from a 50A transfer switch might be a bit much
And here is a picture of my installed one. Ignore the arrow, the terminals in question are to the left of the battery terminals. According to the manual, I should expect currents of about 143A but 16mm sq. is only good for 80A. I toyed with the idea of bigger wire but clearance was an issue. Apparently, those terminals will only take 16mm sq at most. They appear to be M8.
I see the issue now. That does look like little room to spare between those posts.
The transfer relay can handle up to 100A and the inverter can supply an additional 43A due to PowerAssist. This gives teh 143A on the output. But this is only true as long as your circuit feeding the ACin is actually capable of delivering the 100A. I assume thats the case here?
I know theres narrow lugs available specifically for purposes like these, that come with a foot/base that is as wide as the tube part. Personally i would try to use those narrow lugs and a 5x35mm2 cable, while leaving the third phase wire unused. Depending on the length of the cable and how its installed (open cable tray or tightly packed between others) you may be able to use 25mm2.
In any case, i would not reduce the gauge on the neutral. You could argue to reduce the phases, since they can only carry 143A together, so in the best case they both carry half of that, but the neutral always has to carry the full current since its for ACout 1 and 2 combined.
I have heard of those but finding them has proven a challenge. I’m looking for a company that ships worldwide. As a fallback option, I can have them shipped to the US then delivered to me. That’s expensive but what to do. Any recommendations? I wanted to use those with 35 mm².
You have a valid point there.
I may have to reconsider my options.
OGPS
(Ed @ Off-Grid Power Systems - offgridps.com)
6
Hi Fideri,
The US (120V) of the Quattro 10k has the same problem. The studs are too small and spaced too closely together. We’ve also had problems from the factory with the studs snapping off at low torque. For these and other reasons we’ve stopped using the Quattro 10k’s in lieu of using additional Multi-II 48/5000 whenever possible. They consume a lot less standby power and the wiring terminals are much better. Here is a picture of one in a three phase inverter group.
This doesn’t answer your questions, but I wanted to suggest perhaps using different inverters if you don’t need that second AC input. You’ll notice on the Multi-II there are separate neutral terminals for the two AC outputs.
I haven’t helped you, but I would like to ask a favor nonetheless. Can you power up the 10k using a good benchtop power supply without any loads attached to the 10k and tell me what the DC input voltage is and the idle standby current draw is? I’ve been keeping a spreadsheet that tracks actual standby power draw vs published and data for the 10k is missing from my spreadsheet since we rarely use them anymore.
Thank you @OGPS for those ideas. You make some very good suggestions. I’m tempted to switch to Multi IIs, perhaps the bigger ones as I don’t want to parallel the smaller ones, unless I have to. I could use the quattro I already have in another project, as that will be handling fairly low currents.
I will take for you the measurements you need tomorrow. I have batteries and some 250/100 MPPTs. Is that okay for what you need?
I
OGPS
(Ed @ Off-Grid Power Systems - offgridps.com)
8
I’m not sure how accurate that would be, Fideri, but it’s better than the data I have now Thank you.
I can get a DC power supply, though that will take me a bit more time. I guess I need something that can do 48V and perhaps 10A? How will I read the figures off the quattro?
OGPS
(Ed @ Off-Grid Power Systems - offgridps.com)
10
Don’t get anything you don’t already have or need just for this. Thank you for offering. I use a benchtop power supply set at say 51.2V and read the current from the display on the programmable power supply. The voltage isn’t critical so long as you report both the voltage and current. Let the power supply warm up and stabilize and pre-charge the capacitors in the Quattro through a power resistor. Then connect the DC leads of the Quattro to the PS. It won’t needed more than a couple of amps if you pre-charge it. Let it stabilize for 30 seconds or so and then take your readings. Do that three times and average the results.
Victron claims and idle draw of 60W for both the 120V and 230V versions of the Quattro 48/10000. I think it’s closer to 200W but I haven’t tested it on the bench.
Though I haven’t tested it as such, the one I have draws about 120W with no loads.
OGPS
(Ed @ Off-Grid Power Systems - offgridps.com)
12
That’s what another distributor tells me they see, too. But doing the math using numbers presented by VRM made think it was higher. That’s why one of these days I want to actually measure it. I will design around 120W until I find out otherwise. Thank you!
@OGPS I finally did the measurements. The voltage was conclusive but not the current.
Figures:
I measured 54.81 VDC with a DMM and 54.80 VDC with a Cerbo
I measured only 0.01 A with a DMM and 0.0A with a Cerbo!
Testing environment:
I used a Klein Tools RMS DMM
The Quattro 10K was powered by a 250/100 MPPT because I couldn’t find an appropriate power supply.
OGPS
(Ed @ Off-Grid Power Systems - offgridps.com)
14
Thanks Fideri! Did you measure current with a clamp-on ammeter or did you use the probes with internal shunt in the meter? We have a customer with two Quattro 48/5000 120V units powering his off-grid vacation home who is asking for some upgrades for solar and battery. Since we’re going to be there again “soonish” I will send my guys with a benchtop PS and ask them to measure standby power. I suspect that will be more accurate. I’ll add the results to my spreadsheet and send an update.
I have seen one reseller here in the states sell lugs you can install on those terminals. I’m not sure if that’d work in the EU, but if I ever do install a Quattro, I’d likely use the lugs. These are Panduit - LAMA2-14-QY for 2AWG. They have bigger ones if you want to land
Can you power up the 10k using a good benchtop power supply without any loads attached to the 10k and tell me what the DC input voltage is and the idle standby current draw is? I’ve been keeping a spreadsheet that tracks actual standby power draw vs published and data for the 10k is missing from my spreadsheet since we rarely use them anymore.