IBM 3274 51C Maintenance Information page 277

Control Card
r-----------------------------------L------------------------Ju-rn-p--er~----------------~
PTXCP
TPA10
5 1
1000 01
0 0
1
0
0 0
I
0 0
0
TPB07
D
TPA08
o
TPB06 0
TPC030
TP0020
TPA
TPIl
TPC
TPO
TPE
0 0
0
TPEOI
0 0
0
TPFOI
0
0
()
TP(·OI
O
TPF
Jumper
TPG
TPH
0
0 0
TPHOI
0 0
0 TPL07
0 0
0 0 0
TPLOI
0 0
0 0
0 0
0 0
0 0
110 CP
0 0
0 0
0 0
18
B A
~
6 1
1 00
0 01
LEDCP
D
SCP
Figure F-26 (Part 2 of 2). Head/Carriage Replacement
F.3.3 Head Load Solenoid and Bail
F.3.3.1 Solenoid and Bail Service Check (Figure F-27)
1. Power down.
I
DANGER
Voltage is still present at the socket when the power
cable is disconnected.
2. Disconnect the ac drive motor power cable
CD .
3. Insert a diskette, and turn the operator knob
e '
to
the closed position.
4. Power up.
5. To activate the head load solenoid, install a jumper
e
from TPA07 (ground) to the head load TPA08 (-'head
load').
F-34
- - o - o - ' b TPAOI
TPA04
D
TPAMP2 0 0 TPAMPI
SMCP
6
1 0 0 0 0 0 1
D
o
TPCTO
o
TPCT1
14
HCr
1 0 0 0 0 0 0 0 0 0 0 0 0 0 1
6. To deactivate the stepper motor, install a jumper
G
from TPB02 (ground) to TH05 (-'disable stepper motor')'
7. Verify a 0.3 to
0~7
mm (0.012 to 0.028 inch) gap
e
between the bail and the head load arm at each end of
the head movement.
8. Is the gap
OK?
If not, go to Bail Adjustment (paragraph
F .3.3.4, step 5).
9. Remove the jumpers
G
and
0 .
10. Turn the operator knob
G
to the open position, and
remove the diskette.
11. Turn the operator knob
e
to the closed position.
12. Power down.
13. Reconnect the ac drive motor power cable
e.
14. Power up.