Sullair LS-120 series Operators Manual And Parts Lists page 41

keeps on rising or if the modulation does not
begin, adjust the After adjustment, line pressure
should be approximately 126 psig (8.7 bar) and
1.00 in. Hg (2.54 cm Hg.) vacuum below the
inlet.
4. Next, close the service valve; line pressure will
start rising. When line pressure reaches 135
psig (9.3 bar), the inlet valve will be closed to its
maximum position. The inlet vacuum at this
point will be around 25 in. Hg (63.5 cm Hg.). The
machine should unload at this point.
5. Open the service valve so the line pressure is
125 psig (8.6 bar). Machine is now set for oper-
ation. Recheck the unload pressure by closing
of the service valve. Machine should unload via
the pressure switch at 135 psig (9.3 bar).
After the control pressures have been adjusted, the
"unloaded" sump pressure should be checked. It
will be necessary to shut the compressor down,
remove the pressure switch cover, and disconnect
one of the two lead wires that are connected to the
micro-switch (contact block). In order to have a cor-
rect reading, the air system to which the compres-
sor is connected must be pressurized to at least 80
psig (5.5 bar). After disconnecting the lead, tape the
exposed wire with electrician's tape to make sure
that it does not come in contact with any metallic
surface.
DO NOT touch the electrical contacts, terminal or
leads with any metallic object. Severe electrical
shock may occur.
With the lead taped, you may start the compressor
again. Allow the sump pressure to stabilize.
The sump pressure should read 17 to 23 psig (1.2
to 1.6 bar).
Once this is checked, shut the compressor down
once again and reconnect the taped lead and
replace the pressure switch cover. At this time, start
the compressor and cycle the Control System sev-
eral times and re-check all pressure settings and
adjustments.
DO NOT touch the pressure switch, electrical con
with any part of the body or any un-insulated
metallic object. Severe electrical shock may occur.
PRESSURE REGULATOR ADJUSTMENT
Start the compressor and adjust the service valve to
maintain service air pressure at rated pressure (125
psig for example). Turn the adjusting screw on the
regulator until air just begins to escape from the
control air orifice. The regulator is now properly set.
DRIVE COUPLING INSTALLATION AND MAIN-
TENANCE
Refer to Figures 7-6
tion and maintenance the tools required will be a
measuring scale, one set of standard Allen wrench-
es, and one set of standard socket wrenches.
For installation and maintenance of the drive cou-
pling, follow the steps explained below.
Disconnect all power at source, before attempting
maintenance or adjustments.
TABLE 1- INSTALLATION DATA
SERIES 120 & 160 (40-100HP/ 30-75KW)
Coupling
Horsepower Element
40, 50 250004-641 1 13/16"
(37 KW)
60, 75, 100 250018-551
(45, 55, 75 KW)
STEP 1 - MOUNT HUBS
Mount the motor hub and the compressor hub on its
respective shaft.
STEP 2 - COUPLING HUB GAP CHECK
Position the compressor hub, on the compressor
shaft, so that the hub is against
the shaft shoulder and tighten the hub setscrew.
Position the motor hub on the motor shaft and let it
float.
STEP 3 - INSTALL THE FLEXIBLE ELEMENT
Insert the flexible element between the two hubs.
compressed prior to insertion. The element can be
compressed by tightening a suitably sized radiator
hose clamp around the outer edge of the element
as shown in Figure 7-7. Slide the ferry head bolts
Figure 7-6 Drive Coupling "Hub" Gap Check
Section 7
MAINTENANCE
and 7-7. For coupling installa-
Coupling Tightening
Hub Gap Torque (Wet)
55 ft.-lbs.
(46mm) (75Nm)
2 1/16" 110 ft.-lbs.
(52mm) (149Nm)
35