Graco Therm-O-Flow 20 EasyKey NXT 2200 Instructions-Parts List Manual page 37

Cause
With optional light tower, the yellow light illuminates and green light remains on if in Run mode.
Temperature Warning - occurs when a zone temperature is above/below the setpoint +/- warning deviation speci-
fied in the Zone tab of the Setup screen.
Drum Low - occurs when the pail low proximity sensor is activated due to the ram position.
Cause
With optional light tower, the red light illuminates.
High Temperature - occurs when the zone temperature is above the setpoint plus alarm deviation specified in the
Zone tab of the Setup screen.
Low Temperature - occurs when the zone temperature is below the setpoint minus alarm deviation specified in the
Zone tab of the Setup screen while the unloader is in the Run state.
Sensor Error occurs in the following conditions:
• When an enabled zone does not increase in temperature within 7 minutes while the system is in the Heat On
state. This is the short circuit state of an RTD sensor.
• When a zone temperature exceeds 500°F (260°C). This is the open circuit state of an RTD sensor.
Heater Error - occurs if the contactor relay on a temperature board is not closed when a zone of the temperature
board is enabled and in a heat state for the active unloader.
Communication Error - there are two possibilities:
• Start up - Occurs if the EasyKey display board cannot communicate with any board in the system.
• Normal Operation - occurs if any board in the system, including tandem unloader, cannot communicate with the
EasyKey Display board.
Cause
Drum Empty - occurs when the pail empty proximity sensor is activated for the ram position. Pump icon in status
bar starts flashing.
With optional light tower the yellow light begins flashing and the green light turns off.
Pump Runaway - occurs when the pump exceeds the motor shutdown rate set in the advanced tab of the Setup
screen.
The pump icon in the status bar begins flashing.
With optional light tower the red light turns on and the green light turns off.
Maintenance - occurs in advanced unit if user presses maintenance call button. See Maintenance Call Kit
(253548) on page 71 for additional information.
With optional light tower the yellow light turns on.
See Electrical Schematics on page 54 for additional information.
311976A
Table 8: Therm-O-Flow Alarms
Warnings
Alarms
Events
Alarm Troubleshooting
37