BentleyJ
Solar Wizard
Soft starters work quite well on AC condensers, cuts inrush current by up to 70%. I use a HyperEngineering product. There a couple of other brands that have been discussed on the forum as well.
EG4 6k - need help with wiring diagram
- Thread starter ohsolar
- Start date
Subdood
Photon Wrangler
Yeah, I've seen EasyStart units on those Engineer775 (solar installer) videos, they work great from what I've seen. The LRA on my unit is 85A, I believe. I wonder if one of these inverters could start it with one installed (provided there's enough battery and solar).
Were you able to see the before and after current draw on your AC unit with that device?
I updated the diagram. The ground wire -- what guage will that be from main to inverter?
Subdood
Photon Wrangler
Maybe @FilterGuy could comment, he's been helpful in determining how I ought to do my wiring with the 6500 inverter.
BentleyJ
Solar Wizard
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Subdood
Photon Wrangler
I'm guessing 10 gauge should be okay.
How much do the soft starters cost? Does the HVAC person have to be involved?
Subdood
Photon Wrangler
I think they run in the $200-400 range.
I think I could install one, but If you're not comfortable doing it, I'd ask either an electrician or HVAC person to install it.
hmm..yeah, wondering if I should take that risk with the hvac :-(
>8) Is there a discount code that I can apply for if I buy the whole thing together?
any ideas on this? I have seen those affiliate links on some of the youtube videos. What kinda of discounts do they offer?
Subdood
Photon Wrangler
I have worked on a couple outside AC units, they both had bad start capacitors on them. It was an easy repair, but you have to be careful and make sure the power is shut off to the unit. I have electronics experience as that's what I did for 30 years, but this is an electrical job, of which I know a little bit about such things. So, I think I could install an EasyStart unit on one. But, yeah, if you're not comfortable doing that, a pro ought to do it for you.
If you're referring to signature solar discounts, the only one I know of is if you enter "50offcart" in the coupon part of your order. You get $50 off any order $500 or more, so, not much of a discount if you buy a lot of stuff from them.
They had a decent package deal going on around memorial day, where they would give you a certain percentage discount if you bought like a whole system from them, like panels, inverter and batteries. But they haven't had one since then.
If you're referring to signature solar discounts, the only one I know of is if you enter "50offcart" in the coupon part of your order. You get $50 off any order $500 or more, so, not much of a discount if you buy a lot of stuff from them.
They had a decent package deal going on around memorial day, where they would give you a certain percentage discount if you bought like a whole system from them, like panels, inverter and batteries. But they haven't had one since then.
Yeah, not many discounts?.. Eg6k vs 6.5k - need to think thru this..the heaviness of 6.5k is bothering me now?..wish I could just place it inside the rack?
BentleyJ
Solar Wizard
They are fairly straight forward to install if the wiring diagram is carefully followed. However not all manufacturers route L1 & L2 the same way. Goodman for example uses L2 for the C term on the compressor. For single phase the designation of L1 or L2 is somewhat arbitrary but VERY important as far as being able to trace that leg all the way through the system so you do not mistakenly create a dead short.
Lastly, not all HVAC techs are created equal.
One of the new, but slightly used soft starters I purchased on ebay at a great discount, was removed from a working system by the owners HVAC contractor who told him the soft started could not be used on that compressor because it is a "hermetic" type. I had a good laugh because that's just an industry term for the type of compressor used in most all brands. In fact, quite often the capacitor terminal that feeds to the S connection on the compressor is labeled with an "H".
Found my LRA/RLA
AC unit 1 : LRA 124, RLA 18.5
AC unit 2 : LRA 95, RLA 16.5
So I would need an inverter which would at least support 35 amps running. Would 25A per leg handle 35A for the 2 units? (EG 6k)
Guess I would also need to tackle LRA :-(
Some other info I found :
EG4 IDLE Watt:
6k : 115w
6.5k : 70w
AC unit 1 : LRA 124, RLA 18.5
AC unit 2 : LRA 95, RLA 16.5
So I would need an inverter which would at least support 35 amps running. Would 25A per leg handle 35A for the 2 units? (EG 6k)
Guess I would also need to tackle LRA :-(
Some other info I found :
EG4 IDLE Watt:
6k : 115w
6.5k : 70w
BentleyJ
Solar Wizard
Quick clarification of the amperage issue. A split phase inverter that supplies 25A per leg at 120V still only supplies 25A at 240V. Your confusing Watts with Amps.
The formula is V x A = Watts.
25A x 120V = 3000W and 25A x 240V = 6000W
Here is the counter intuitive part. If you put a 3000W, 120V load between L1 and Neutral, you get 25A of current in both L1 and N. If you then add another 3000W load on L2 and Neutral you do not get 25A on each of L1 & L2 and 50A on the Neutral, you get 25A on L1 and L2 and ZERO amps on the Neutral. It is worth contemplating this concept in order to fully understand what is going on.
Bottom line: 35A at 240V is 8400W so a 6kW inverter is not going to work even with a soft starter.
The formula is V x A = Watts.
25A x 120V = 3000W and 25A x 240V = 6000W
Here is the counter intuitive part. If you put a 3000W, 120V load between L1 and Neutral, you get 25A of current in both L1 and N. If you then add another 3000W load on L2 and Neutral you do not get 25A on each of L1 & L2 and 50A on the Neutral, you get 25A on L1 and L2 and ZERO amps on the Neutral. It is worth contemplating this concept in order to fully understand what is going on.
Bottom line: 35A at 240V is 8400W so a 6kW inverter is not going to work even with a soft starter.
Subdood
Photon Wrangler
Well, each of his units draw less than 25A by themselves, so do you think this 6k inverter with its big transformer could start one of them without a soft start?
I checked the label on my unit, its LRA is 75A, RLA is 18A, so running power is about 4kW. So, same question. I'm asking this with the presence of say 5kW of solar, and a 5kWh battery.
I've noticed that the wiring that comes from the outdoor unit has the two hots going into a 30A double pole breaker on our home's main panel, but what looks like a white neutral wire goes to the ground bar with the other green ground wires. Our house panel is not the service panel, it's outside on the pole, so unlike the service panel, the main panel's ground and neutral bars aren't bonded. I thought that odd that the neutral wire from the AC unit went to the ground bar.
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I think I will need to read up a bit :-( Basically I want to offset one of units grid power with power from batteries to save on monthly bills.
For example, I want to run unit #2 with as much battery as possible during the day.
AC unit 2 : LRA 95, RLA 16.5
so from your statement, 16.5A * 240v = 3960w
Are these statements correct?
1) So a 6000 watt inverter should be able to handle this as long as it can start it, right?
2) And if I have 2 eg4 5k batteries, it should be able to run this for couple of hrs
3) to start the AC unit, I would need to take care of surge power which is 95A with a soft start. What do I need to get this down to run unit #2? 25A?
Thank you for all the answers..it is enlightening
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Subdood
Photon Wrangler
I'm not speaking for Bentley, but regarding question 3, you don't necessarily have to get the start current down to 25A, because the large transformer in the 6k inverter can handle big current surges briefly. They should be able to handle a 2x (50A) surge. If you have sufficient battery power, which you're saying you'd have about 10kWh, then I think it would start it without much problem with a soft start installed, IMO. But, these EG4 batts don't seem to like big current spikes, so I could be mistaken.I think I will need to read up a bit :-( Basically I want to offset one of units grid power with power from batteries to save on monthly bills.
For example, I want to run unit #2 with as much battery as possible during the day.
AC unit 2 : LRA 95, RLA 16.5
so from your statement, 16.5A * 240v = 3960w
Are these statements correct?
1) So a 6000 watt inverter should be able to handle this as long as it can start it, right?
2) And if I have 2 eg4 5k batteries, it should be able to run this for couple of hrs
3) to start the AC unit, I would need to take care of surge power which is 95A with a soft start. What do I need to get this down to run unit #2? 25A?
Thank you for all the answers..it is enlightening
Regarding question 1, I'd say yes you're correct.
Regarding question 2, theoretically you could run the AC unit for about 2 hours, but the battery manufacturer doesn't recommend such a large continuous load (30A or 1500W max per hour per battery). 4kW in an hour out of two batteries would be about 80A (4000W/50VDC) out of them, or 40A for one, which it should handle, but may shorten the life span of the battery.
#2. AC usually does not run for 2 hours continuous. It will start/stop and maybe run for 1 hour during a 2 hour period (maybe less). So theoretically, it could power for 4 hours (with 10kwh)..just guessing here
>But, these EG4 batts don't seem to like big current spikes, so I could be mistaken.
hmm..Did you see that in some doc/video?
I will add #4 here:
1) This video shows the inverter out coming into the sub-panel main lug without a breaker and powering the rest of the circuits
so in the sub-panel below, is the 40A the main lug breaker? Do you have picture of your setup?
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