Roberts Gorden UltraVac NEMA 4 - Manual (Page 38)

ROBERTS GORDON ® ULTRAVAC™ C ONTROLLER I NSTALLATION M ANUAL
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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
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:
Step 7.1.6 Return to the PC and click the vacuum
pump and three zones to "AUTO", then click exit.
Parameter
Number
Parameter
Name
Factory
Default
New
Setting
P05 Standard
Speed
Source
01 03
P45 Speed at
Minimum
Signal
0.0Hz Frequency
Setting noted in
Section 7.1.3
P46 Speed at
Maximum
Signal
60.0Hz Frequency
Setting noted in
Section 7.1.2
Record Frequency Setting Here: