Wood’s Powr-Grip MRTALP611LDC - Manual (Page 34)

Rev 10.0/5-14 32 MRTALP6-DC: #35056
V
ACUUM
S
WITCH
A
DJUSTMENT
Vacuum Switch Function
Two vacuum switches control various functions of the vacuum lifter (see OPERATING FEATURES
for location of vacuum switches). While the lifter is powered up, each vacuum switch senses the
vacuum level in one of the two vacuum circuits of the vacuum system. If either circuit loses
significant vacuum while the lifter is in the apply mode, the system responds automatically.
Each vacuum switch controls two functions: Settings n_1 and n_2 control the vacuum pump(s)
and the battery gauge. Settings n_3 and n_4 control a vacuum lift light and low vacuum
warning buzzer, light and/or strobe light.
Both vacuum switches should have the same settings to ensure the two circuits are functioning
together. Although the vacuum switches are set at the factory and should not require
adjustment, the following section lists the factory settings, in case adjustment is necessary.
Adjustment Procedure
WARNING: Lifting capacity decreases whenever vacuum switch is adjusted to
maintain lower vacuum level.
1) To unlock the vacuum switch settings, press and hold the “SET”
button for at least five seconds. Note that a different menu may
appear if the button is released too soon. 25 Use the arrow keys to
access the unlocked mode (“UnL”) and press the “SET” button again.
2) Press and release the “SET” button to access the different settings
(n_1, n_2, n_3, n_4). Use the arrow keys to adjust each setting and
then press the “SET” button to continue to the next setting. The
following values should appear on the digital display:
• n_1 = -458. This setting turns off power to the vacuum pump(s)
when the vacuum system reaches the maximum vacuum level.
Setting n_1 must always be set above n_2.
Note: Lowering this value allows the pump(s) to shut off at higher elevations, but it also
requires the pump(s) to run more frequently.
• n_2 = -425. After a vacuum switch has turned off the vacuum pump(s) (see n_1) and the
vacuum system begins to lose vacuum, setting n_2 turns on power again to the vacuum
pump(s). The vacuum pump(s) should turn on before the needle on either vacuum gauge
moves from the green range to the red range. Setting n_2 must always be set above n_4.
25
The vacuum switch has additional settings that should not be adjusted. These settings are accessed if the “SET” button is
held for 3 seconds. For reference, the correct settings are provided below.
• Setting 1 should display “nnH”
• Setting 2 should display “1nC”
• Setting 3 should display “2nC”
• Setting 4 should display “192”
• Setting 5 should display “nAn”