![background image](http://html1.mh-extra.com/html/graco/therm-o-flow-plus/therm-o-flow-plus_instructions-manual_2251607015.webp)
15
309085
Installation
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.
Sensor Resistance Checks
WARNING
ELECTROCUTION HAZARD
To reduce risk of injury or damage to
equipment, conduct these electrical
checks with the main disconnect OFF.
The package includes up to eight heat sensors and
controllers for each of the heated zones. To check
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
).
RTD Sensors
Zone Component Terminals
Value Range
1
Ram Plate
2161 & 2171
97.4 – 102.8
ohms
2
Dispense
Hose 1
2231 & 2241
97.4 – 102.8
ohms
3
Dispense
Hose 1
2301 & 2310
97.4 – 102.8
ohms
4
Dispense
Gun 1
2371 & 2381
97.4 – 102.8
ohms
5
Dispense
Hose 2
2561 & 2571
97.4 – 102.8
ohms
6
Dispense
Gun 2
2631 & 2641
97.4 – 102.8
ohms
7
Dispense
Hose 3
2661 & 2671
97.4 – 102.8
ohms
8
Dispense
Gun 3
2731 & 2741
97.4 – 102.8
ohms
Summary of Contents for Therm-O-Flow Plus
Page 22: ...22 309085 Notes...
Page 28: ...28 309085 Advanced Pendant Control Screen Map TI0683 See Next Page...
Page 30: ...30 309085 Notes...
Page 43: ...43 309085 Notes...
Page 60: ...60 309085 Service For 400 480 and 575 VAC Supply Units Junction Box Schematic Fig 18 TI0673...
Page 61: ...61 309085 Service For 240 VAC Supply Units Junction Box Schematic Fig 19 TI0673...
Page 65: ...65 309085 Notes...