Agilent Technologies U1251A manual Square Wave Use 53131A Output, Use 34410A

7 Performance Tests and Calibration

Step		Test Function	Range	5520A Output	Error from nominal 1 year
					U1251A	U1252A
19	Press	button to go to	5 A	5 A, 1 kHz	± 42 mA	± 37 mA
		A mode
			3A	3 A, 5 kHz	± 96 mA	± 96 mA
			10 A [11]	10 A, 1 kHz	± 100 mA	± 90 mA
			Square Wave	Use 53131A
			Output
20	Turn the rotary switch to the		120 Hz @ 50%		N/A	± 26 mHz
		position
			4800 Hz @ 50%		N/A	± 260 mHz
		Duty Cycle	100 Hz @ 50%		N/A	± 0.398% [12]
			100 Hz @ 25%		N/A	± 0.398% [12]
			100 Hz @ 75%		N/A	± 0.398% [12]
				Use 34410A
		Amplitude	4800 Hz @		N/A	± 0.2V
			99.609%

Notes for verification test:

1The additional error to be added as frequency > 20 kHz and signal input < 10% of range: 300 counts of LSD per kHz.

2The accuracy could be 0.05% + 10, always use relative function to zero thermal effect (short test leads) before measuring the signal.

3The accuracy of 500 W and 5 kW is specified after the Null function.

4For range of 50 MW, the RH is specified for < 60%.

5The accuracy is specified for < 50 nS and after Null function as open test lead.

6All frequency counters are susceptible to error when measuring low voltage, low-frequency signals. Shielding inputs from external noise pickup is critical for minimizing measurement errors.

7Use the Null mode to zero residual.

8The accuracy does not include the tolerance of the thermocouple probe. The thermal sensor plugged into the meter should be placed in the operating enviroment for at least an hour. Use the Null function to reduce the thermal effect.

9Always use relative function to zero the thermal effect with open test lead before measuring the signal. If you do not use Relation function, add 20 digits for accuracy purposes.

1010 A continuous and additional 0.5% to specified accuracy when measuring a signal greater than 10 A~20 A for 30 seconds maximum. After measuring current for > 10 A, to cool down the meter for twice the measuring time you applied before low current measurement.

126 Agilent U1251A/U1252A User’s and Service Guide