I installed mine in 1996 after hurricane Luis...cat5 in antigua for 48 hours. It has been great. Today I finally replaced the main pcb and a few months ago i replaced the end unit with the fancand power connectors. I cant find anything with all the features of the sw4024 and I don't think the performance has been exceeded up to now, The main failure mode used to be fans ducting dirt and moisture over the main control pcb wrecking the left hand side copper Mine lasted 25 years ..I took great care to minimize dirt and damp getting to the fans.
Trace SW 4024 inverter users
- Thread starter SolarfortheOuachitas
- Start date
Thats a good question. If the gen fails to start 3 times and youre not around, that's it. It won't try again/
I would like to know exactly what batteries you had, and how the charging was set up, using temp sensors? Do they ever get completely discharged?
RCinFLA
Solar Wizard
- Joined
- Jun 21, 2020
- Messages
- 3,563
The old SW Trace inverters do not have direct DC current regulation for battery charging. They adjust charging current based on input AC current monitoring to inverter.
Best way to set charging current is doing battery charging power divided by inverter efficiency to get power required from AC input. Since battery voltage typically rises during charging the bulk DC current will drop off a bit as battery charges.
For example, to get 120 amps DC of charging into 24.8v battery you want close to 3 kW's. 3 kW / 92% inverter efficiency requires 3.3 kW's from 120vac mains input. 3,300 watts / 120vac = 27.5 amps AC setting for AC input charging current.
You have to have max AC input current limiting set equal or higher then chargng AC input current otherwise the charging will be limited by max AC input current settng level. If AC output loads consume some of the allowed maximum AC input current then the left over will be given to battery charging.
To avoid over discharging battery you set the battery low voltage shutdown. Just be aware of any voltage drop you have in battery cables.
The other thing about old SW inverters is without battery present the inverter AC input relay has no coil power so even if grid or generator is present there will be no output AC power or charging. This is very important if converting to LFP with a BMS that can pull the battery supply.
Best way to set charging current is doing battery charging power divided by inverter efficiency to get power required from AC input. Since battery voltage typically rises during charging the bulk DC current will drop off a bit as battery charges.
For example, to get 120 amps DC of charging into 24.8v battery you want close to 3 kW's. 3 kW / 92% inverter efficiency requires 3.3 kW's from 120vac mains input. 3,300 watts / 120vac = 27.5 amps AC setting for AC input charging current.
You have to have max AC input current limiting set equal or higher then chargng AC input current otherwise the charging will be limited by max AC input current settng level. If AC output loads consume some of the allowed maximum AC input current then the left over will be given to battery charging.
To avoid over discharging battery you set the battery low voltage shutdown. Just be aware of any voltage drop you have in battery cables.
The other thing about old SW inverters is without battery present the inverter AC input relay has no coil power so even if grid or generator is present there will be no output AC power or charging. This is very important if converting to LFP with a BMS that can pull the battery supply.
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tkilpatrick
New Member
- Joined
- Dec 25, 2020
- Messages
- 3
Can anyone point me to some instructions as to how to wire the RY7 and RY8 relays on the SW4024 for generator control? Is there a plug that goes onto the three prongs and if so where do I order one? I have the module to the generator I just don't know how to plug into the inverter relays. Thanks for your help.
I installed my 4024 in 1996, right after hurricane Lewis in Antigua. It ran for 20 years without a hitch, and has since had a main board and the end board with fans and connections which finally succumbed to tropical corrosion. I doubt if there is anything available now as good. It’s a total solution in one box.
The one thing which gets them in the end is corrosion where the fans duct raw air over the boards. Do everything to make sure that air is clean and dry in all weathers.
You use ordinary 1/4 inch female push on crimp connectors, one prong at a time. Any car or marine shop with accessories et has them. The three relays provide for different generator hook up systems along with the setup menu. You must study the manual to get it right.
dougbert
Solar Addict
Do you have a source or link to a replacement fan for the sw4024
I installed my trace in 1999, used mostly for UPS operation. In 2018 I have switched to OFF grid mode where I use the grid for battery backup only. Doing that has caused the fan to be used more often, so I want some backups in my parts bin
thanks
Sorry, I retired from being an agent for Trace among many other marine equipment, and had a set of PC boards, now all used. I saw earlier in this forum someone referred to a guy in Seattle who rebuilds. Anyway I'm going to look at an old fan and maybe get the OEM and model for you.
tkilpatrick
New Member
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- Dec 25, 2020
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- 3
I've got the SW4024 to remote start the generator but have been unable to get it to AutoStart using the exercise function. I've checked everything but I'm obviously missing something. I've set the exercise days to 01 which should cause the generator to be autostarted everyday but nothing is happening. Any ideas would be appreciated.
tkilpatrick
New Member
- Joined
- Dec 25, 2020
- Messages
- 3
Yep I got it to start the generator so I believe I have the RY7 wired correctly. What it won't do so far is Auto start the generator. I've set the exercise days to 01 which should cause it to turn the generator on everyday to exercise it but so far nothing.
Yes a SW4024 owner here. Bought in 1999. Used sparingly over the years then we replaced batteries and added some upgrades recently. All good after dialing in the new settings. Yesterday after a charging and float session, when I switched it from FLT back to LBX, it went dead just dark. No noise/ spark /click/ nothing. It was not inverting at the time, and it did not blow the AC in breaker at the panel. The one external breaker on the left end didn't seem to trip, so I must go deeper. Any theories? We have not been working it very hard.. I will post elsewhere later to not hijack thread but this was a general 4024 thread at first I think. ADDED 7-22- Roy at sun pumps taught me that the 50 amp fuse from the batteries was too small and that 200-250 was desirable with our 4/0 wire size. 30 bucks later all good thanks Roy!
THX.
THX.
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I want to coopt my SW4024’s RY7 to control a 240Vac relay (or two 120 Vac) that will connect my solar trailer battery to the instead of my diesel generator. I want to automate it using the Trace inverters’ generator control. Can I power the relay with 24Vdc and simply go through COM and NC on the RY7 connector?
Background: I took over an off grid location with 2x Trace SW4024 in Series for 120/240Vac dual production; one is stamped 1994 (original install) the other 2002 (replaced then, I heard that original got fried). A 2011 Hawker Powerline forklift battery and a 2kW array of 1993 PV panels. There is also a 1998 Bergey 1.5kW windmill and a power management box by Photon where all the wiring comes together. A 1989 Diesel Generator supplies backup (manual start)
The original setup is still working great and powers a large weekend residence with a 36000 gallon pool and hot tub combo that use two var.speed Pentair pumps for moving and filtering all that water, about 8kWh per day for that part alone (heating uses gas). Recently I’ve been using the old diesel generator’s AC input to hook up a solar trailer instead using diesel during the sunny months. The PV trailer produces about 8kWh per day on average april-oct; it has a midnite classic charge controller and 2 SMA sunnyboys 6048 working two sizeable battery banks (lead acid). Still wrapping my head around the trailer capacity. Basically I let it charge all day, then connect it to the house as a generator around 6pm, let it run for 1-2 hours. This replenishes the house battery for nighttime stuff and gives it an extra boost for all the loads the next day (pool pumps, DC well Pump, power tools charging, house needs).
I sure would like to get this all working on auto. The house battery should draw from the solar trailer battery when it needs to, and the solar trailer should stop giving when battery reaches 50% depleted - Im thinking there’s a way to set up the SMA 6048 to limit that.
Rod I think reachable through " Sun Pumps" is very knowledgeable and seems to know about parts. he helped me a lot via phone. i believe he had actually worked there back in the day.
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SolarfortheOuachitas
New Member
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- Aug 1, 2020
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Good morning. Does anybody have a Trace SW 4024 or 4048 or similar model for sale?
I’m looking to create a new off-grid system and am an old-school guy and want to work with something that I’m familiar with.
Thanks!
danadams2008
New Member
danadams2008
New Member
How old are the sws that do not have the feature your talking about?