Preferred FlexFit 110 User Manual

Parameters 4-65
FlexFit – Linkageless Control – Revision 1.0
PREFERRED
UTILITIES MFG CORPORATION
PP
AA
RR
AA
MM
EE
TT
EE
RR
SS
Figure 4 – 2
×
 
= + +
 
 
TOTAL UP DOWN
A L
V V V
1728
( ) ( )
( ) ( )
= =
= =
3 3
TOTAL UP
3 2
DOWN
V Pipe Train Volume ft V Upstream Valve Outlet Cavity Volume ft
V Downstream Valve Inlet Cavity Volume ft A Total Pipe Area in
( )
=L Pipe Length in
Valve Train Volume Calculation
Next, determine the test time seconds using the formula in "Figure 4 – 3 Test Time Calculation". Round up this value to the next
higher second and enter it into the appropriate parameter – "P1.3.10 Fuel1 Leak Test Sec" or "P1.3.12 Fuel2 Leak Test Sec". The
minimum test time is 10 seconds.
Figure 4 – 3 Test Time Calculation
= × ×
TOTAL
P
Test Time 187,000 V
C
( )
( )
= =
3
P
Supply Pressure to Upstream Valve psi C Burner Capacity ft hr
( )
=
3
TOTAL
V Pipe Train Volume ft
Timing Calculation Example:
Variable Description Example Value
V
UP
Upstream Valve Outlet Cavity (ft
3
) 0.0441
V
DOWN
Downstream Valve Inlet Cavity (ft
3
) 0.0554
D Pipe Diameter (NPT inches) 3
A Pipe Area (in
2
) (from Table 4 – 1) 7.393
L Pipe Length (in) 22
P Supply Pressure (psi) 6.4
C Burner Capacity (ft
3
/hr) 7954
Table 4 – 2 Gas Leak Test Timing Calculation Example Data
Figure 4 – 4
×
 
= + + =
 
 
3
TOTAL
7.393 22
V 0.0441 0.0554 0.1940 ft
1728
= × × =
6.4
Test Time 187,000 0.1940 29.190 seconds
7954
⇒ =Round up to next highest time in seconds Gas leak test time 30 seconds
Gas Leak Test Timing Calculation Example
P1.3.9 Fuel1 leak teSt oPtIon
Menu > Advanced Settings > Flex Sequences > Flex Gas Leak Test Password Level: Engineer Restricted? Yes
This is enabled when fuel 1 valve leak testing is required.
Options: Disabled: Leak testing is not used or required
Post Purge: Leak testing is performed after post purge. If a limit opens during the post purge leak test or it can't be
completed for some other reason, the FlexFit will instead perform a leak test pre-purge.
Post & Pre Purge: Leak testing is both performed after post purge and pre-purge.
P1.3.10 Fuel1 leak teSt Sec
Menu > Advanced Settings > Flex Sequences > Flex Gas Leak Test Password Level: Engineer Restricted? Yes
This determines the leak test duration (seconds). After venting/pressurizing the test section, this is the time delay to detect a pressure
rise/fall due to a Safety Shutoff Valve (SSOV) leak.
Options: 10 to 90 [Default 60]

Preferred FlexFit 110 Specifications

General

Brand	Preferred
Model	FlexFit 110
Category	Controller
Language	English