Temperature Control

Fault: messages

The message displayed when this occurs is shown in Figure 3•6.

Figure 3-6

ACTUAL SETPOINT

WARN: OVEN SHUT OFF

Message, Oven SHUT DOWN

The oven remains off until switched on again via the keyboard

( OVEN TEMP ON ), unless a FAULT: message is displayed (see below,

Fault: messages). Power to the instrument must be switched off, and then on again to restore operation (setpoints are maintained).

Fault: messages

Figure 3•7shows possible FAULT: messages associated with heated zones or the oven. In general, the following problems are indicated when a FAULT: message appears:

CADC OFFSET indicates a problem with one or more electronic components in circuitry associated with temperature control.

CLINE SENSE indicates a problem with AC power to the instrument (an excessively high source voltage).

CAny of the TEMP RDG messages indicate an inoperative temperature sensor for the indicated zone or oven.

COVEN > MAX + 20 indicates oven temperature exceeds the current OVEN MAX setpoint value by more than 20^C. Thermal run•awayis the likely cause.

Note: In case multiple problems exist simultaneously, press CLEAR to roll through all message displays.

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