Keysight E3630A, Руководство по эксплуатации и обслуживанию

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Service Information 5
Keysight E3630A Operating and Service Manual 51
Rated output and ammeter accuracy
6 Connect two 40 Ω 20 W load resistors across both of the 20 V outputs of the
supply and set the ±20 V VOLTAGE control for ±20 V outputs. (All supplies
must be fully loaded while checking the rated output voltage and current of
each supply.)
7 Connect the test setup shown Figure 5-4 to the +6 V output. Make the total
resistance of R
L
and the current sampling resistor equal to 2.4 Ω to permit
operating the output at full load. R
L
should have a power rating of at least
20 watts.
8 Close the switch and set the +6 V VOLTAGE control so that the DVM indicates a
voltage drop across the current sampling resistor that corresponds to a current
of 2.5 amps.
9 Push the +6 V METER switch and verify that the front panel ammeter indication
is within ±(0.5% + 2 counts) of 2.5 amps (2.47 A to 2.53 A).
10 Check the rated output and ammeter accuracy of the +20 V and –20 V
supplies similarly by connecting the test setup of Figure 5-4 to each output in
turn. For each 20 V supply: make the total resistance of R
L
and the current
sampling resistor 40 Ω , set the ±20 V VOLTAGE control for a current indication
on the DVM of 0.5 A, check that the panel meter indication is within ±(0.5%+2
counts) of 0.5 A (0.48 A to 0.52 A).
11 Disconnect all loads from the supply.
12 Connect the test setup shown in Figure 5-4 to the +20-volt output. Substitute
a short for R
L
and leave the load circuit switch open.
13 Set the voltage of the ±20 V supplies to 20 volts.
14 Close the load switch and determine the current flow through the current
sampling resistor (meter shunt) by measuring its voltage drop with the DVM.
The current should be 0.55 A ±5% (0.5225 A to 0.5775 A).
15 Check the current limit of the –20 V supply in the same way. Its short-circuit
current should also be 0.55 A ±5% (0.5225 A to 0.5775 A).
16 Connect the test setup shown in Figure 5-4 to the +6 V output. Close the
switch, set the total resistance of R
L
and the current sampling resistor to an
initial value of 2.4 Ω or greater, and set the output voltage to 6 volts.