Hypertherm DuraChill 5 HP Air-Cooled Chiller For Hypertherm - Manual (Page 16)

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5.8 Low Temperature Limit (LL)
This menu item also serves a dual function. First, it establishes the minimum allowable set point temperature and
thus helps prevent an operator from inadvertently setting the temperature set point below a pre-established
temperature. Secondly, it serves as a low temperature alarm, automatically activating both audio and visual alarm
indicators when the measured fluid temperature drops to the LL setting. The compressor, heater, fan, and pump will
also turn off.
To change the low temperature limit value, rotate the Select/Set Knob until the desired value is displayed on the
temperature display.
LL 4 .0
NOTE: See Section 4.6.1 for freeze protection requirements .
5.9 High Ambient Temperature Limit (HA)
This menu item protects the Chiller from overheating due to a high ambient temperature. Should the ambient
temperature rise above the limit value, the audio and visual alarms will activate and the compressor, heater, fan, and
pump will turn off.
To change the high ambient temperature limit value, rotate the Select/Set Knob until the desired value is displayed on
the temperature readout.
NOTE: This value is always displayed and set in °C.
HA 45
5.10 Lower Temperature Band (Compressor Turn Off)
This menu item provides access to the Lower control band value. This is the amount below set point that the process
temperature can drop before the compressor turns off. It is useful at heat loads less than 30% of full capacity. The
highest setting of 5.0
°C will give longest compressor life.
Lb 5 .0
NOTE: See Section 4.6.1 for freeze protection requirements.
5.11 Upper Temperature Band (Compressor Turn On)
This menu item provides access to the Upper control band value. This is the amount above set point that the process
temperature can raise before the compressor turns on. It is useful at heat loads less than 30% of full capacity. The
highest setting of 5.0
°C will give longest compressor life.
Ub 5 .0
5.12 Temperature Calibration Offset (c1)
This menu item allows you to adjust the Chiller’s displayed temperature reading to match that of a traceable standard.
It allows you to offset the displayed temperature value by as much as ±1.9°C.
NOTE: Calibration offset values are always set and displayed in °C. To prevent the operator from accidentally
changing the calibration offset, a special sequence of keystrokes is required to access this function.
1. Press and hold the Units/Menu Button until HL appears on the display.
2. Press and release the Units/Menu Button until
Ub appears on the display.
3. Press and hold the Units/Menu Button.
4. While holding the Units/Menu Button, press and release the Select/Set Knob.
5. When
CAL appears on the temperature readout, release the Units/Menu Button. The current calibration
offset value will appear on the temperature readout. Notice that the display will alternate between the offset
value and the calibrated temperature.
6. Rotate the Select/Set Knob until the desired calibration offset is displayed. Press the Select/Set Knob or
simply allow the display to time out to accept the displayed value.
c1 0 .0