Monday, January 17, 2011

Surge Protector Installation - Shore Power and Generator

This articles describes the installation of a Surge Guard protector in a RB so that it monitors both shore power and generator power.

Starts by unplugging the rig from 120 VAC shore power.
Shut off all 12 volt power, including removing the solar panel fuse.

In cabinet under the refrigerator next to the converter, remove the plywood panel on the left side to expose converter and water heater. There are 4 flathead screws.

Remove converter front cover.

Remove screws mounting converter to cabinet and then pull the converter out.

On the back of converter is the transfer switch. You are interested in the two wires (black and white) that exit the transfer switch and enter the converter. This is inside the converter box.

The white wire goes to a bus bar on the left side of the converter box.

The black wire goes to the 30-amp breaker.

Remove both the black and white wires.



Mounting the Surge Guard was a challenge. There was plenty of room in beside the converter, but the Surge Guard also had to be mounted so that we could see the LED status lights. I finally decided to install it in a cut-out of the side panel of the cabinet. That way we merely open the cabinet door if we need to check the lights. Using some scrap pieces of lumber I made a mounting board which was securely fastened in place. When the Surge Guard was mounted, its face was flush with the side panel and just fit into a hole I cut in the panel.



Looking at the inside of the converter, on the left side next to the bus bar that the white wired went to, you see two round metal knock-outs.

Knock both of them out and install 2- 1/2" romex clamps.

Cut two 4' sections (or longer, it depends on where the Surge Guard is mounted) of 10-gauge romex. On all the ends of the romex, trim the cover and expose 4-5" of the three wires, strip ends ~3/4".

Install one end of each piece into each side of the Surge Guard. Black is hot, white neutral and copper ground on the terminal strips. You might want to label each piece to help keep things sorted out. I labeled the two pieces of romex, one "input", the other "output", so that I would not get them mixed up.

Run 'Input' side romex to converter, enter thru one of the romex clamps. Use wire nuts to joint 'Input' black to black wire (the one removed earlier from the breaker)

The 'Input' white wire is jointed, with a wire nut, to the white wire that was removed from the bus bar. The bare copper wire goes to the ground bus bar, located at the top of the converter box.

The 'Output' romex is wired inside the Surge Guard the same as the 'Input'.

Black to hot, white to neutral, ground to ground.

The other end of the 'Output' romex is fed thru the remaining romex clamp.

Black wire goes to where the original black wire was removed from the 30-amp breaker.

White wire goes to the neutral bus bar where the original white was removed.

Copper ground goes to ground bus bar at top of converter case.


Tighten the romex clamps. Make sure the wire nuts are tight and taped.

Tighten all wire connections on the breakers and bus bars.

Reinstall converter into cabinet, mount cover.

Turn on the power and look for smoke. If no smoke, consider it a successful installation.

Contributors: Larry Wade, WxToad

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