148-0598 Rev. A
Page 9
May 1998
will automatically advance to the next
mode in about 5 sec.
5.2.7
The display will read CAL.H.
Press and release the push button. The
display will read C_20 if you have
previously selected d-4C, or C__1 if you
have previously selected d-6C.
5.2.8
With the pressure is exactly 20
Torr (DV-4) or 1 Torr (DV-6) press and
release the push button. This stores the
tube output in memory and advances to
the next mode.
5.2.9
The display will read CAL.L.
Press and release the push button. The
display will read C0.01 (d-4C) or C.001
(d-6C).
5.2.10
Evacuate the gauge tube to
0.01
Torr
if d-4C was selected or to
0.001
Torr
if d-6C was selected.
5.2.11
Press and release push button.
The display will indicate
0.01 Torr
if
d-4C was selected or
0.001 Torr
if d-
6C was selected. This stores the tube
output in memory and returns the
MODEL 4/6 to its normal measuring
mode.
5.2.12
This completes the custom
calibration.
5.3 REFERENCE
TUBE
CALIBRATION
The low end of the vacuum range can be
set with a
Hastings Reference Tube
,
such as the
DB-16D
which is used with
the DV-4 range, or the
DB-20
is which
is used with the DV-6 range. The DB-
16D should have a marked calibration
value between 0.01 Torr and 0.20 Torr.
The DB-20 should have a marked
calibration value between 0.001 Torr and
0.010 Torr. (1 to 10 millitorr)
You do not need access to the push
button for this calibration procedure.
5.3.1
Connect the Reference Tube to
the AVC module. Turn the MODEL 4/6
ON. You are in the normal measuring
mode. Wait about 1 minute.
5.3.2
The display should read the
pressure marked on the Reference Tube.
NOTE:
Some DB-16D Reference
Tubes may be marked in
mmHg
and
some DB-20 Reference Tubes may be
marked in
microns Hg
. or
millitorr
. To
convert:
1 mmHg =
1 Torr
1 micron Hg =
0.001 Torr
1 millitorr
= 0.001 Torr
5.3.3.
If the displayed pressure does not
match the pressure marked on the
Reference Tube, adjust the
potentiometer marked
Pmin
on the top
of the AVC module until they agree. Do
not confuse Pmin with the potentiometer
marked S.P. also located on the top of
the AVC module.
5.3.4.
This completes the Reference
Tube calibration.
6.0 MAINTENANCE
The only authorized maintenance at the
user level for the MODEL 4/6 is
replacement of the ¼ amp fuse in the ac
line connector.
7.0 TROUBLE
SHOOTING AND