TROUBLESHOOTING GUIDE
50A Surge Guard
Surge Guard* RV power products protect your RV from low quality or incorrect shore power.
Normally, shore power should be around 115 –120 Volts AC from L1 or L2 to Neutral, or 240V from L1 to L2. When power
falls too far outside this range it represents a poor or hazardous condition to your RV's electrical system. Surge Guard RV
power protection products provide protection to your RV by turning off power when the line voltages L1 or L2 fall below
102 Volts AC or go above 132 Volts AC.
Surge Guard devices also protect your electrical system from a reverse polarity condition which indicates that the hot and
neutral lines of shore power are swapped or reversed. This can be hazardous to equipment and safety. The Surge Guard
device will not connect power to your RV until the Reverse Polarity fault is corrected.
In the event your Surge Guard device is not functioning as expected, perform the following troubleshooting steps in order
to determine and correct any malfunctions. Note: Testing should be performed with AC units and electrical appliances
turned off, then verified with appliances turned on.
Connect the shore power cord to a 240V, 50A power source. The Caution When Flashing light will blink on and off for at
least 128 seconds before power is connected to the RV. This allows the Surge Guard device to correctly determine the line
voltages before applying them to the RV. If you also have the optional remote LCD display, the screen will display "DELAY"
plus the delay time for 128 seconds while the Surge Guard device is monitoring the incoming power and the caution light
is flashing. Note that this guide also applies if using 120V, 30A power with a suitable adapter.
MODEL 35550 INDICATOR LIGHT GUIDE
CONDITION
DESCRIPTION
Normal Conditions
Startup Condition
Reverse Polarity
Open Ground
Voltage on Ground
Over or Under Voltage
No Power at L1
PROBLEM
Coach powers up after 128 seconds but then
turns off after another 8-10 seconds.
L1 or L2 light turns red.
For technical assistance, please call 1-800-780-4324 x 20311
Manufactured by Southwire Company, LLC, 5250 140th Avenue North, Clearwater, Florida 33760
Model 35550
Hardwire Portable Device
*
INDICATOR LIGHT STATUS
LINE 1
green
on
on
on
on
red
off
TROUBLESHOOTING STEPS
The Surge Guard device may be operating properly, and you may have a low voltage condition.
If so, turn off as many loads as possible. It is not safe to operate some equipment with low
voltage. Verify that the input voltage L1 and L2 are greater than 102VAC with loads turned on
and off.
You have an under or over voltage condition on Line 1 or Line 2 coming into the RV. If these
lights are green, yet you do not have power after 128 seconds on the remote display and the
Caution light remains blinking, then you must inspect your shore power for a reverse polarity or
open conductor fault. These faults will also be visible on the optional remote display if used.
© 2017 Southwire Company, LLC. All rights reserved.
LINE 2
DELAY/CAUTION
green
off
on
flashing
on
flashing
on
flashing
on
flashing
red
flashing
off
off
* Trademark of Southwire Company, LLC. Registered in the United States.
LINE
POWER ON
CAUTION WHEN FLASHING
LINE 1
(Green = OK, Red = Fault)
LINE 2
(Green = OK, Red = Fault)
SURGE
(No Protection When Lit)
REMOTE
PORT
Model 35550
120/240V, 50Amp
3850 Joules of Power Surge Protection
LOAD
* Trademark of Southwire Company, LLC. Registered in the United States.
RV POWER
on
off
off
off
off
off
off
505-00117B