Agilent Technologies 669xA Enabling the Calibration Mode PASWDl, Calibrating the OVP Trip Point

Table A-2. Typical Front Panel Calibration Procedure

		Action		Display Response
	Enabling the Calibration Mode			PASWDl
1.	Begin calibration by pressing	.
2.	Enter calibration password from Entry keypad.
	If password is correct the Cal annunciator will come on.			PASSWD ERROR
	If password is incorrect, an error occurs2.
	Note: The initial (factory-default) password is the model number of the power supply,
	but it can be changed (see "Changing the Password" in Appendix A - Calibration).
	Entering Voltage Calibration Values
1.	Make certain the DVM is the only load on the power supply.			(Meter mode)
2.	Select the first calibration point by pressing		.	VRDG1
	If the power supply is not in CV mode, an error occurs3			WRONG MODE
3.	Read the DVM and use the Entry keypad to enter the first voltage value.			(Meter mode)
4.	Select the second calibration point by pressing		again.	VRDG2
5.	Read the DVM and use the Entry keypad to enter the second voltage value.			(Meter mode)
	Note: If one of the entered values is not within acceptable range, an error occurs.			CAL ERROR
	The power supply is now holding the new voltage calibration constants in RAM.
	Calibrating the OVP Trip Point
1.	Make certain the voltage has been calibrated and there is no load on the power supply.			(Meter mode)
2.	Select OVP calibration by pressing	.		OVPCAL
3.	Wait for the power supply to compute the OVP calibration constant.			CAL COMPLETE
	If the supply goes unregulated or into CC mode during OVP calibration, an error occurs.			NOT CV MODE
	If the computed constant is out of acceptable range, an error occurs.			DOES NOT CAL
	Wait for the power supply to compute the new OVP calibration constants, which will be
stored in RAM.
	Entering Current Calibration Values
1.	Make certain appropriate shunt resistor (see Table A-l) is the only load on the power supply.			(Meter mode)
2.	Select the first calibration point by pressing		.	IRDG1
	If the power supply is not in CC mode, an error occurs.4			WRONG MODE
3.	Wait for DVM reading to stabilize. Then read DVM and compute the first current value			(Meter mode)
	(DVM reading ⎟ shunt resistance).			(Meter mode)
4.	Use Entry keypad to enter the first current value.
				IRDG2
5.	Select second calibration point by pressing		again.
6.	Wait for DVM reading to stabilize. Then read DVM and compute the second			(Meter mode)
	current value (DVM reading ⎟ shunt resistance).			(Meter mode)
7.	Use Entry keypad to enter the second current value.
	Note: If the entered value is not within acceptable range, an error occurs.			CAL ERROR
The power supply is now holding the new current calibration constant in RAM.				CAL COMPLETE

1. If CAL DENIED appears, then an internal jumper has been set to prevent the calibration from being changed. (See the Service Manual.)

2. If the active password is lost, the calibration function can be recovered by moving an internal jumper that defeats password protection. However, this also will change all calibration constants to their factory-default values. (For more information, see the Service Manual.)

3. Program the output current to 10% of its rated output*

4. Program the output voltage to l0% of its rated output*

* See applicable Output Ratings in "Chapter 1- General Information"

98 Calibration