TB 9-6625-2354-35
Table 14d. Simpson, Model 270-4 Resistance
Calibration Performance Limits and Adjustments
Resistance
Test instrument
Resistance standard indications
Test instrument
1
(Ω)
Indications
Resistance
ohms scale
Min
Max
Adjustments
(Ω)
range
2
RX1
12
11.2
12.9
RX100
12
1130
1260
None
RX10,000
12
113,000
126,000
TI must be calibrated in horizontal position.
1
2 Short
leads and adjust OHMS ADJ for 0 indication on ohms scale. Repeat for each range.
Table 14e. Simpson, Model 270-4 Dc Current
Calibration Performance Limits and Adjustments
Dc Current
Test instrument
Calibrator
Test instrument
1
Indication
Initial output
err indication
Adjustments
Dc current range
(A)
(A)
(%)
(fig. 5) (R)
50 A
50 A
50 A
1.25
R1
2
1 mA
1 mA
1 mA
1.75
R2
10 mA
10 mA
10 mA
1.75
----
10 mA
6 mA
6 mA
2.91
----
10 mA
2 mA
2 mA
8.75
----
100 mA
100 mA
100 mA
1.75
----
500 mA
500 mA
500 mA
1.75
----
10 A3
10 A
10 A
1.75
----
TI must be calibrated in horizontal position.
1
Connect positive lead to TI +50A/250mV input. After 50 A check is complete, move positive lead to TI + input.
2
3 Connect TI negative lead to -10A input and connect TI positive lead to +10A input.
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