Wiring Samlex PST-300 Watt Inverter; ran into a snag!

2oldman wrote:

Ron3rd wrote:
... if you wiggle the wire at all it pops out. .. connection is very weak due to the small set screw. .

For any long-term operation I think you're going to have to mount the inverter securely, and do a very careful job of strain-relief on the cables.

That's what I'm going to do. Right now if you wiggle the #6 at all it pops out due to the small set screw.

Ron3rd wrote:
... if you wiggle the wire at all it pops out. .. connection is very weak due to the small set screw. .

For any long-term operation I think you're going to have to mount the inverter securely, and do a very careful job of strain-relief on the cables.

I've had a similar experience with a Prosine 2.0 -not your bottom of the barrel device. The hard-wire version had #12 pigtails on the ac side. That's really cutting it close for a 2,000 watt inverter.

2oldman wrote:

Ron3rd wrote:
... 4, 6, or 8 gauge wire depending on the length of run. No way will any of those sizes fit directly to the inverter

That is odd. If a #10 fits, then they sized it for 30 amps.

Actually, I was able to get the #6 in the hole after carefully rounding off and smoothing the strands but it was very tight. The set screw is so small that if you wiggle the wire at all it pops out. Not your standard lug with big set screw. So I guess the 6 or 8 will work but the mechanical connection is very weak due to the small set screw. The cables supplied have a little flat metal tap that goes in the round hole. One of the cables is #12 (the one with the battery alligator clips) The cigar lighter plug cable is even smaller.

Ron3rd wrote:
... 4, 6, or 8 gauge wire depending on the length of run. No way will any of those sizes fit directly to the inverter

That is odd. If a #10 fits, then they sized it for 30 amps.

2oldman wrote:
If your 12v run is less than 6', you should be fine snipping wire strands. According to the manual, anyway, and the guy you spoke to.

Funny thing is, according to the manual, you should run 4, 6, or 8 gauge wire depending on the length of run. No way will any of those sizes fit directly to the inverter and it seems it's not really designed to be hard wired but is designed to run either of the accessory cables I mentioned in my original post. The set screws that hold the wire in the hole are very small such that you almost need an eyeglass screwdriver to tighten.

Thanks for all the good info. I'm only running an LCD tv off it for now so I might temporarily rig it up by snipping the strands. When I get back, I'll do the copper tubing/solder thing, never thought of that.

If your 12v run is less than 6', you should be fine snipping wire strands. According to the manual, anyway, and the guy you spoke to.

I would not be snipping any strands off. Nor would I ever use Wire Nuts to make any connection in a moving vehicle.

The proper way to handle this is to either use a wire lug with the right size hole... Or...Make some up using Copper Tubing . You could also use washers ,but make sure that You tighten the Lug Nuts and use lock washers or Use locking nuts.

To make wire lugs using Copper Tubing :

Cut a length of copper Tubing two and a half to three times the length of the stripped wire end.

Using a Vice squeeze one end of this tube flat . Drill the correct size hole through the flattened end to attach it to the lug. Grind the flattened end to round it off or remove sharp corners.

Slip the tubing onto the stripped wire and secure it using a centre punch to crimp and Solder .

I would use coloured Shrink Wrap to seal the job!

Go to hardware store. Purchase ONE FOOT LENGTH of copper tubing sized to fit your #6 wire. Yes it needs to be crimped and soldered.

Cut off a length suitable to make your own terminal.

In a VICE squeeze shut about a half inch of one end of the tubing.

FILE the inverter end to fit the terminal. Lots of side to side material removal. Copper is soft.

With a wire brush you bought at the hardware store, clean the INSIDE and outside of your new terminals, new copper penny bright.

Fit the tube end onto your cable, crimp then solder.

When soldering, apply it all over the copper tube terminal. All over. It's OK to use paste flux.

Apply appropriate heat shrink tubing to prevent lugs from touching each other.

Took longer to write this than it does to actually do it.

MrWizard wrote:
Number 4 ga is larger than #6ga
No way would #4.. be borderline.. that might be over kill
Depending on length , #8 might be borderline and create too much voltage drop for a full load on the inverter

Agreed.