At a campground, a Power Watchdog reported that the trailer did not have a neutral and repeatedly cut power. The Pebble charger worked when plugged in directly at the highest amperage on a 50A connection. Has anyone else seen this behavior with a Power Watchdog?
Do our Pebbles not have a neutral connection? The Scout AI product says no neutral in Pebble. Is this an issue in any camping or shore-power situations?
The Pebble has a neutral on the internal panel, but connecting an EVSE is very different from connecting a standard RV power cord. With an RV cord, two hot leads, neutral, and ground connect to a circuit-breaker panel. An EVSE charger, such as the Pebble charging cord, is the actual load device; it provides a single 240V feed through the J1772 connector to the Pebble charging system and battery. The breaker panel is fed from the high-voltage battery inverter and has no direct connection to the pedestal outlet other than ground. This design is not a safety issue, but traditional RV tests will not have the same results.
Does any of that make our units less vulnerable to damage from surges, open grounds, or other issues typically seen on campground pedestals? I want to protect the Pebble and an EV that may be plugged into it while the Pebble is connected to a campsite pedestal. Given all this, is a surge protector needed between the pedestal and trailer, and what type is best?
Classic RV issues such as “hot skin” are not really possible with the way the Pebble is connected. Pebble put conditioning and surge suppression in the charger, so it will protect the Pebble from pedestal issues including surges, short of a lightning strike.
I use a PWD50 Gen 1 to protect the Pebble charger. If the Watchdog burns up protecting the Pebble charger during a trip, I still have a working charger while I replace the Watchdog surge module. If the Pebble charger absorbs the surge, I have no campground charger until Pebble ships a replacement.
A Rivian charger can also work as a backup charger for the Pebble. It does not have the ability to downgrade current like the Pebble EVSE, but that should be irrelevant with a 50A pedestal. I tested the Rivian EVSE on the Pebble and the Pebble EVSE on the Rivian; both worked fine.
I have not tested a 30A connection with an adapter. Also, my 30A dogbone adapter supplied by Pebble did not work, while an older adapter I had for the Rivian worked fine. Test all adapters and configurations at a campsite when you can, especially if the pedestal has 50A, 30A, and 15A outlets.
Good info—I will test all today.
Good tip about EPO. That probably explains why some have reported their Watchdog working fine while others have had no success. Mine is the plain PWD50.
Which type of Watchdog do you have: surge-only or surge + EPO (emergency power off)? We have both kinds, and the EPO model won’t work with our Pebble or the Rivian. Same issue: it doesn’t think there’s a good neutral. Something about the emergency power-off function doesn’t seem to like EVSE chargers. The surge-only Watchdog works fine.
It is the surge + EPO model. I’ll see if I can swap it out. Thanks for the response.
I just ordered the 50A Power Watchdog with EPO—guess I need to cancel. Cancelled order.
I bought the Gen 2 Power Watchdog without EPO and used it for the first time this past weekend. Once connected to the Pebble EVSE, it turned red and gave error E8 for missing neutral on the RV. However, it continued to power and charge the Pebble. I know this relates to Pebble’s electrical setup and that the EPO model is not compatible. Is this normal behavior for the non-EPO model?
The Gen 2 seems to check for a few more conditions. The error is technically correct because EVSE chargers, not just Pebble’s, use the two hot legs and ground with no neutral connection. EPO units cut off power when they detect this condition. Yours is still providing power, so you should be fine as long as that is the only error displayed.
Thanks for confirming.