Graco 311511G Over Temperature Alarms, Fluid Heater Temperature Offset, Hose Heat Manual Mode

Models: 311511G

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Initial Startup

Over Temperature Alarms

Both the fluid heater and the hose heat have over temperature alarms that will turn off the heat zone if high temperatures are detected. If this happens, the green light in the switch for that heat zone will go out.

The fluid heater has a fixed temperature switch on the aluminum heater that opens at 230 °F (110 °C) and turns off the heat zone. The temperature switch will automatically reset, but the heat zone will need to be manually restarted. The over-temperature condition should never happen unless the solid state relay (165SSR) fails closed.

The hose heat uses the temperature controller alarm, monitoring the hose thermocouple (FTS) to watch for high temperature conditions. This alarm is controlled by SP2 (Set Point 2) and is factory set for 30 °F (17 °C). This means that the alarm set point is 30° (17 °C) over the SP1 operating temperature set point. Under normal conditions, the output 02 light will be lit on the hose controller. This output holds the hose heat power contact ON and lights the green light in the switch any time power is available to heat the hose. If the hose temperature reading is 30 °F (17 °C) (SP2 setting) over the temperature set point (SP1), the output 02 light and switch light will go out. Hose heat will only return after a manual START of the control switch, after alarm conditions are gone.

The hose heat deviation alarm is controlled by the SP2 setpoint. This is factory set to 30 °F (17 °C) and should not be changed. A loss of alarm function and loss of automatic over temperature shut-down could result.

Fluid Heater Temperature Offset

The fluid heater has been calibrated to provide setpoint temperature fluid under flow conditions. When the machine is powered up and no heat has been turned on, the heater display will read somewhat lower than the hose display. This is normal. The hose display has no offset and will always read the actual temperature at the sensor in the hose.

Hose Heat Manual Mode

If the hose temperature controller does not see the Fluid Temperature Sensor (FTS), it will shut off the hose heat and give a flashing error alternating between:

SbEr = Sensor break error

H20.0 = Heat output 20%

The hose can be manually heated by turning the hose back on with the hose switch and green light. The up/down arrows can be used to adjust the default 20% power output.

There is no monitoring or alarm in manual mode. You must monitor the temperature by inserting a probe thermometer inside the hose insulation against the hose. The thermometer will read 10-20 °F less than actual fluid temperature. Repair the temperature sensor or cable as soon as possible to avoid damaging the heated hose.

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311511G

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Graco 311511G important safety instructions Over Temperature Alarms, Fluid Heater Temperature Offset, Hose Heat Manual Mode