Wood’s Powr-Grip P2110445DC - Manual (Page 13)

Rev 22.0/5-13 11 P2-04-DC: #35113
Reading the Vacuum Gauges
Each vacuum gauge indicates the current vacuum level in the vacuum system for one pad
channel. The green range indicates vacuum levels sufficient for lifting the maximum load
weight, whereas the red range indicates vacuum levels that are not sufficient for lifting the
maximum load weight. Both gauge needles should show a sudden surge in vacuum as the
vacuum pads seal against the load. If it takes more than 5 seconds for the vacuum level to
reach 5" Hg [-17 kPa] on either vacuum gauge, press on any 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 both vacuum gauges, except when used at high
elevations (see SPECIFICATIONS: Operating Elevation). If not, make sure both vacuum
switches are adjusted correctly (see MAINTENANCE: V
ACUUM
S
WITCH
A
DJUSTMENT
). If either
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 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 both vacuum gauges, due to leakage in the seal
between the vacuum pads and the load surface. 5 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
: Cleaning), and reapply the lifter to the load. If the load has rough or porous
surfaces, the operator must conduct a test to determine whether the lifter is designed
to lift the load , as follows:
1) Make sure the vacuum generating system for each pad channel is 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, disconnect the electrical connectors uniting the
batteries with the vacuum generating systems.
Note: After the test is completed, move the valve handles to the “RELEASE” position (power
off ) before reconnecting the batteries.
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 vacuum level of 10" Hg [-34 kPa] on both vacuum gauges
during this time. If not, the load does not possess the characteristics required for using
this lifter. 6
5
Contaminated loads can also cause the vacuum pumps to run frequently or continuously. Since excessive pumping quickly
reduces battery energy, the operator should clean the load when possible, to minimize pumping.
6
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.