Fluke 5725A Analog Monitor Section, STANDBY VOLTAGE LIMITS1, Signal, Physical, Source, Purpose

5725A

Instruction Manual

latch up by eliminating positive feedback resulting from positive output voltages from U100. Op amp U105 is simply a low-noise inverting amplifier that scales the sensor output to 10 dB below the 5700A Oscillator output level. The output of the calibration circuit, AC/AC, goes to the 5700A during calibration through the analog monitor section.

4-56. Analog Monitor Section

The 16-channel multiplexer, U151, takes a variety of inputs from all analog assemblies and provides a means of switching them to either a comparator, U154A, or to the B-RCL line via K152. During normal operation, the multiplexer output is routed exclusively to the comparator. Calibration requires routing the multiplexer output to the B-RCL line, which is routed back to the 5700A. The B-RCL line is measured by the precision adc circuit on the 5700A DAC assembly. All inputs to the multiplexer are scaled so that inputs are within its ±15V power supply range. Table 4-4 shows the signal name of the multiplexer input, its description, origin, and purpose.

The state of the multiplexer is controlled by the microprocessor via data latched into U152.

STANDBY VOLTAGE LIMITS(1)

Table 4-4. Signals Monitored by the Analog Monitor Section

SIGNAL	PHYSICAL	SOURCE	PURPOSE
NAME	PARAMETER

-0.125V	+400V IM	Supply Current	Power Supply	Monitoring
+0.125V	-400V IM	Supply Current	Power Supply	Monitoring
0.26V	+400V M	Supply Voltage	Power Supply	Monitoring
-0.26V	-400V M	Supply Voltage	Power Supply	Monitoring
⎯	VCOM	System Supply Common	Power Supply	Monitoring
⎯	HVCOM M	High Voltage Supply	Power Supply	Monitoring
		Common
1.7V	HVTEMP M	Voltage Amp Heat Sink	High Voltage Amplifier	Monitoring
		Temp.
2.0V	ITEMP M	Current Amp Heat Sink	Current Amplifier	Monitoring
		Temp.
-2.2V	ICOMPL M	Current Output Stage	Current Amplifier	Monitoring
		Drive Level
⎯	I CAL/I FB	Shunt Voltage	Current Amplifier	Calibration, AC I
				Operation
⎯	AC/AC	Calibrator Output	High Voltage Sense	Calibration
⎯	HVSENSE	Sense Amp Output	High Voltage Sense	Calibration
⎯	DAC OUT	DAC Output	High Voltage Sense	Monitoring
0.08, 2.0V	FAN M	Fan is On or Off	Power Supply	Monitoring

Note 1: For single limit values, the limit is equal to, or smaller in magnitude to, the value shown.

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