Check The Resistance Between The Supply Unit And The True Earth Ground; Checking Resistance - Graco Therm-O-Flow Plus 243698 Instructions-Parts List Manual

Check the Resistance Between the Supply
Unit and the True Earth Ground
WARNING
FIRE, EXPLOSION, AND ELECTRIC
SHOCK HAZARD
To reduce the risk of fire, explosion, or
electric shock the resistance between
the supply unit components and true
earth ground must be less than 0.25
ohms.
Have a qualified electrician check the resistance
between each supply unit component and the true
earth ground. The resistance must be less than 0.25
ohms. If the resistance is greater than 0.25 ohms, a
different ground site may be required. Do not operate
the system until the problem is corrected.
NOTE: Use a meter that is capable of measuring re-
sistance at this level.

Checking Resistance

WARNING
ELECTRIC SHOCK HAZARD
Do not open the electrical control panel,
unless you are a trained professional.
Before opening the control panel, make sure that
all power has been removed from the control panel.
You can check the resistance of the supply unit's heat
sensors and heaters.
12 309213
Installation
Sensor Resistance Checks
To verify the RTD sensors to be used with the 2- or
4-zone heat control box, refer to the tables below.
RTD Sensors – 2-Zone Control
Zone Component Terminals
1
2
RTD Sensors – 4-Zone Control
1
2
3
4
An ohm meter can be used to check the resistance
between the terminals indicated. To check the sensor
resistance:
1. Make sure the power is off and that the disconnect
switch is in the OFF position.
2. Make electrical resistance checks for the
components.
3. Replace any parts whose resistance readings do
not comply with the ranges listed in the chart
below.
NOTE: Check resistance at ambient room tempera-
ture (63_ – 77_ Fahrenheit
WARNING
ELECTROCUTION HAZARD
To reduce risk of injury or damage to
equipment, conduct these electrical
checks with the main disconnect OFF.
Dispense 1091 & 1101
Hose 1
Dispense 1161 & 1171
Gun 1
Dispense 1161 & 1171
Hose 1
Dispense 12631 & 1241 108 + 2%
Gun 1
Dispense 1301 & 1311
Hose 2
Dispense 1371 & 1381
Gun 2
).
Value Range
108 + 2%
ohms
108 + 2%
ohms
108 + 2%
ohms
ohms
108 + 2%
ohms
108 + 2%
ohms