Wood’s Powr-Grip PCFT2SA47 - Manual (Page 20)

Rev 0.0/11-13 18 P2-DC2: #35114
B3
B2
Reading the Vacuum Gauges
Two vacuum gauges on each pad channel display the current vacuum levels
in positive inches of Hg and negative kPa for both circuits of the dual
vacuum system.
The operator must read the vacuum gauges on both
pad channels. Each gauge's green range indicates vacuum levels sufficient
for lifting the maximum load weight (see figure B2), whereas the red range
indicates vacuum levels that are not sufficient for lifting the maximum load
weight (see figure B3). If it takes more than 5 seconds for the vacuum level
to reach 5" Hg [-17 kPa] on a vacuum gauge, press on any vacuum pad that
has not yet sealed.
Vacuum Level on Optimal Surfaces
When the lifter is attached to clean, smooth, nonporous load surfaces, it
should be able to maintain a vacuum level in the green range on all vacuum
gauges, except when used at high elevations (see SPECIFICATIONS:
Operating Elevation). If not, make sure all vacuum switches are
adjusted correctly (see DIGITAL VACUUM SWITCH ADJUSTMENT in SERVICE
MANUAL for details). If any vacuum switch cannot be adjusted to maintain a
vacuum of 16" Hg [-54 kPa], perform the V
ACUUM
T
EST
(see MAINTENANCE)
to determine whether there is a deficiency in the corresponding vacuum
generating system.
Vacuum Level on Other Surfaces
When the lifter is attached to contaminated, rough or porous load surfaces, it may not be able to
maintain a vacuum level in the green range on all vacuum gauges, due to leakage in the seal
between the vacuum pads and the load surface.
14 In the case of contamination, thoroughly
clean the contact surfaces of the load and the vacuum pads (see MAINTENANCE: V
ACUUM
P
AD
M
AINTENANCE
: Pad Cleaning), and reapply the lifter to the load. If the load has rough or porous
surfaces, the operator must conduct a load suitability test , as follows:
1) Make sure the vacuum generating systems for both pad channels are functioning correctly
(see MAINTENANCE: V
ACUUM
T
EST
).
2) Apply the vacuum pads to the load as previously directed.
3) After the vacuum pumps stop running, place the power switches for both pad channels in the
OFF ( ) position.
4) Raise the load a minimal distance, to assure that it is supported by the lifter.
5) Monitor the vacuum gauges while the load is suspended for 5 minutes:
The lifter must
maintain a minimum level of 10" Hg [-34 kPa] on all vacuum gauges during this
time. If not, the load does not possess the characteristics required for using this lifter. 15
14
Contaminated loads can also cause a vacuum pump to run frequently or continuously. Since excessive pumping quickly
reduces battery energy, the operator should clean the load when possible, to minimize pumping.
15
Certain load materials are too rough or porous to allow the lifter to form a seal which can be maintained for 5 minutes without
power. However, in geographical locations where CE Standards do not apply, it may be possible to use the lifter to lift such loads.
Contact Wood’s Powr-Grip for more information.