Card Checkout - Keithley 199 Instruction Manual

MAINTENANCE
WARNING
The cover plate must be installed if the scan-
ner card is removed.
4. Remove the two quick-disconnect terminal blocks from
the scanner card before installation.
5.~0rient the scanner card above its final location (see
Figure 6-12), and plug the ribbon cable (PI) into the
mating receptacle (J26) on the analog board (see Figure
6-Q). The red mark on the ribbon cable must be
oriented on the right as viewed from the front of the
unit.
6. Put the scanner card into the unit so that it lines up
with the rear panel slot and is adjacent to the grooves
in the case side.
7. Secure the scanner card to the rear panel with the two
screws removed in step 2.
8. Secure the scanner card to the analog board using the
supplied #6-32 x l-1/8" screw.
WARNING
The screws must be installed to ensure proper
grounding. The analog board shield must not
9.
10.
11.
12.
Connect one end of the supplied two-conductor ca-
ble to J30 on the scanner card, and the other end to
J29 on the digital board.
Move Jumper W2 to position B as shown in the illus-
~tE?tiO*.
Using a pair of diagonal cutters, cut jumper W3 on
the digital board (see Figure 6-13 for location). This -
step is necessary to enable scann$r card operation.
Replace the case cover and bezel, and secure them
with the screws removed earlier. Proceed to the fol-
lowing paragraph to check out the scanner card to
verify that it is operational.
6.8.2 Card Checkout
Use the procedure below to test the functionality of the
Model 1992 after installation.
1. Connect a short jumper wire between the H and L ter-
minals of each channel input on th-e hvo terminal
blocks.
2.Xonnect the A and B outputs together (H to H, L to
L), and then connect the outputs to the VOLTS OHMS
Hl and LO terminals on the rear panel (H to HI, L tom
ID). Use the supplied output cables.
3. Plug the connecting blocks into the scanner card, and
make sure the front panel INPUT switch is in fhe rear
position.
4. Plug in the Model 199 and turn on the power.
5. Press the SCANNER button, and verify that the follow-
ing message is displayed:
CHANNEL?
6. If, instead, the unit displays the "NO SCANNER'
message, you may have forgotten to cut jumper W3 as
described in paragraph 6.8.1.
7. Press 0 to return to normal display.
8. Select the following Model 199 operating modes.
Function: OHMS
Range: 3ocQ
Resolution: 5% digits.
Filter: off
zero: off
9. Te?npo?arily short the rear panel VOLTS OHMS ter-
minals, then press ZERO. Leave zero enabled for the
remainder of the checkout procedure.
10. Press SHIFT TRIG SETW, and use uprange or
downrange so that the "ONE SHOT" trigger mode
message is displayed.
11. Press NEXT twice to return to normal display.
12. Press SHIFT SCAN SFNP, then NEXT twice to
display the present scan mode. Use uprange or
downrange to display the following:
STEP
X3. Press NEXT to completeprogramming.
14. Press SCANNER and note that the instrument displays
the following:
LIMIT?
15. Press 8 to program the limit.
16. Press TRIGGER to close channel 1. The inswanent will
display the resistance reading on channel 1.
77. Verify the resistance reading is less than lfi.
18. Press TRIGGER to cycle to the next channel. Verify that
the resistance reading is less than 10.
19. Repeat step 18 for the remaining channels.
20. If all channels show an overflow reading in its test, hit
is probable that the cad was installed improperly (refer
to paragraph 6.8.1). If only one channel measures
im-
properly, check to see that the channel jumper is in-
statled properly.
6-23