Roberts Gorden UltraVac NEMA 4 Installation Manual page 38

ROBERTS GORDON ® ULTRAVAC™ C
Step 7.1.3 After setting end vent vacuums between
2.5" wc and 3.0" wc, while all the burners are still
operating, use the down arrow button on the VFD to
reduce the frequency of the output signal to the
pump. Reduce the frequency of the VFD until the
manometer at each of the end vents reads 1.0" wc -
1.2" wc Make note of this frequency setting below.
The frequency is found on the VFD's LCD screen.
1.0" w.c. - 1.2" wc VFD Frequency Setting
Record Frequency Setting Here:
Step 7.1.4 Return to the PC and click the pump and
zones to "OFF".
Step 7.1.5 Using the procedure described in on Page
27 , Section 6.1.1 through Section 6.1.5, alter the fol-
lowing parameters on the VFD:
Parameter Parameter
Number Name
P05 Standard
Speed
Source
P45 Speed at
Minimum
Signal
P46 Speed at
Maximum
Signal
Step 7.1.6 Return to the PC and click the vacuum
pump and three zones to "AUTO", then click exit.
32
I M
ONTROLLER NSTALLATION ANUAL
Factory New
Default Setting
01 03
0.0Hz Frequency
Setting noted in
Section 7 .1.3
60.0Hz Frequency
Setting noted in
Section 7 .1.2