HP 3457A Service Manual page 136

c. Use the following procedures to calibrate the DC Current offset on the 300 uA, 3 mA, 30 mA,
300 mA and 3 A ranges beginning with the 3 A range. & |
1. Set the 3457A to the appropriate current range. (Use the { or | scroll key to select the proper range.)
2. Access the Calibration Command. (Press the Blue SHIFT key, then the OFFSET COMP / C configura-
tion key.) The display will show CAL.
3. Enter the value of the input - in this case 0. (NOTE: If the security feature has not been disabled (set to
0), it will be necessary to 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.
e. Repeat steps "cl " through " c4 "for each of the remaining ranges.
5-62. CALIBRATION PROCEDURES - HP 44492A 10 CHANNEL MULTIPLEXER ASSEMBLY
5-63. Wiring Block Preparation
5-64, It will be necessary to connect a shorting wire to the Plug-In Assembly Wiring Block before calibra-
tion can be performed. The following procedure outlines the wiring block preparation.
WARNING
This procedure assumes that the Wiring Block is new and has no wires connected to
it. If the Wiring Block is connected to an external device, hazardous voltages may =
be exposed when the Strain Relief /Wiring Block Assembly is removed.
fi Ge UG Qh UG Oh Of Of OG Oh a
© SAN
44492A RELAY
SHORTING WIRE
Figure 5-5. 44492A Wiring Block Connections
a. Remove the two screws attaching the Strain Relief/Wiring Block Assembly to the rear panel and dis-
connect it from the instrument. (Refer to Figure 5-3, Step 1).
b. Remove the Strain Relief Plate from the bottom of the Strain Relief Assembly (Figure 5-3, Step 2). &
5-18