YellowBuddy
New Member
- Joined
- Aug 9, 2020
- Messages
- 59
Assuming you have a Sunny Island, Right there on page 60:
"Default settings of the relays
Relay 1 is preset to the "AutoGn" generator start function and relay 2 to the "AutoLodSoc" load
shedding function."
As another poster said, 300 pages of German instructions and not one picture of a girl.
The relay has NO and NC contacts. The "normally" position (with Sunny Island off or unpowered) has the load shed. Under normal operation with decent charge remaining on battery, the NO contact of relay 2, which by default is "load shed", gets closed and can control a relay. At default 70% DoD it sheds the load. I finally located the SMA version of a power relay. It is 3PST, 100A per contact, and has 48V coil. I had it shipped from Europe.
(almost) any relay can be used. The relays in SI can handle AC or DC for pilot duty. SI has a 48V (actually battery voltage) terminal available, with 0.5A PTC fuse. The big power relays you will find take WAY more than 0.5A, and the SMA version is no different. At least one I checked (if not the SMA) had a 10 ohm coil. That draws 5A! 250W! but only for milliseconds; as soon as it closes a fourth contact opens. The relay has two windings for the coil, second one being very high resistance for "hold" but not "pull in". The fourth contact switches the coils before PTC fuse opens, so current draw greatly reduced.
Oh the SI is the easy part. I'm more thinking about how to setup the panel. Right now my SB and SI combine in the same panel - my critical loads panel. So to add a load shed, I'd need to wire the relay in before the loads - and space is tight. Hence why the figure out the wiring. I've got a combiner panel for my (2) SB's, so that will most likely be the place to relocate the SI breaker to the combiner.