Temperature Control

After a power failure . . .

Figure 3-7

ACTUAL SETPOINT

FAULT: ADC OFFSET

ACTUAL SETPOINT

FAULT: LINE SENSE

ACTUAL SETPOINT

FAULT: INJA TEMP RDG

ACTUAL SETPOINT

FAULT: DETA TEMP RDG

ACTUAL SETPOINT

FAULT: OVEN TEMP RDG

ACTUAL SETPOINT

FAULT: OVEN > MAX+20

Thermal Control FAULT: Messages

In addition to the message, the red NOT READY LED blinks. All zones and the oven are turned off and made inoperative until power is switched off, and then on again (setpoints are maintained).

After a power failure . . .

Setpoint values are protected during a power failure (even if intentional, by disconnecting the power cord, or by switching off the HP 5890 at its main power switch) by a lithium battery (10•yearnominal life) which maintains power to HP 5890 memory.

After power is restored, a message is displayed, as shown in Figure 3•8.

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