Dc Volts Offset Calibration - HP 3457A Service Manual

Calibration 3457A
a. Remove the two screws attaching the Strain Relief/Wiring Block Assembly t o the rear panel and
disconnect it from the instrument. (Refer t o Figure 5-3, Step 1).
b. Remove the Strain Relief Plate from the bottom of the Strain Relief Assembly (Figure 5-3, Step 2).
c. Remove the Wiring Block from the Strain Relief Mousing (Figure 5-3, Step 3).
d. Install copper shorting wires from INput HI t o INput LO, from INput HI t o Sl Sense HI, and from
INput LO t o
R
Sense LO on 4-Wire ! 2 input channel 10. Securely tighten the appropriate retaining
screws. (Refer t o Figure 5-4 for wire connections).
e. Connect the prepared Wiring Block Assembly to the I-IP 44491A General Purpose Relay Assembly.
SHORTING WIRES
/
@
RELAY
Figure 5-4. 44491A Wiring Block Connections
5-58. DC Volts Offset Calibration
-
HP 44491A
a. Select the DC Voltage function.
(Press the DCV function key).
b. Select the Scanner Input.
(Press the T E R M configuration key, enter the number 2 and press the E N T key).
C.
Select channel 0.
(Press the C H A N configuration key, enter the number 0 and press the E N T key).
d. Use the following procedure t o calibrate the DC offset on the 300 V, 30 V, 3 V, 300 mV and
30 mV ranges beginning with the 300 V range.
1. Set the 3457A t o the appropriate range.
(Use the
or
&
scroll keys t o select the proper range).
2. Access the Calibration Command.
(Press the Blue S H I F T key, then the OFFSET C O M P
/
C
configura-
tion key).
The display will show CAL.
3. Enter the value of the input
-
in this case 0.
(N07'h': If the security feature has not been disabled (set t o
0 ) , i t will be necessary t o enter the input value, the delimiter
(
,
)
and the security code).
4. Press the ENT key. The display will show CALIBRATING while the calibration routine is
running.