VESDA by Xtralis
VESDA VFT-15 Product Guide
www.xtralis.com
19
10.0
PROGRAM
0.01
0.1
1.0
4.0
SCAN
ISOLATE
F1 . . . Fn
SOUNDER
SILENCE
ACCEPT
CODE REQUIRED
20.0
000 .. . 999
STOP
TEST
MENU
RESET
?
000
FIRE 1
ALERT
ACTION
FIRE 2
FAULT
ALARM
SECTOR
1
3
2
4
5
6
8
10
9
7
ALL
12
15
13
14
11
B
C
A
D
Legend
A
Detector
B
Normal diameter Microbore tube
C
Reduced diameter Microbore tube
D
Reducer connector
Figure 3-6: Configuration with reduced diameter Microbore tube
Table 3-8 below lists the length requirements for the normal and reduced diameter tubes for different distances
between the detector and the sampling location (hole).
Distance between Detector
and Sampling Location (Hole)
Microbore Tube Length
Normal Diameter
Reduced Diameter
7.5 m (25 ft)
0 m (0 ft)
7.5 m (25 ft)*
16 m (52 ft)
10 m (33 ft)
6 m (20 ft)
24.5 m (80 ft)
20 m (66 ft)
4.5 m (15 ft)
33 m (108 ft)
30 m (98 ft)
3 m (10 ft)
41.5 m (136 ft)
40 m (131 ft)
1.5 m (5 ft)
50 m (164 ft)
50 m (164 ft)
0 m (0 ft)
Table 3-8: Tube Length Requirements
* 0.1m (0.33ft) normal tube is required to connect the reduced diameter tube to the detector inlet port
Unused inputs on the detector should be looped to one another using short lengths of normal diameter
Microbore tube. For example, if the VFT-15 detector has unused inputs 9 to 15, one way of connecting the
unused inputs would be to use short pieces of microbore to connect inputs 9 to 12, 10 to 13, 11 to 14 and have
input 15 capped off.
Example: Determine New Tube Configuration for a 33 m (108 ft) distance to sampling location (hole)
Solution (as per Table 1):
l
Normal diameter Microbore: 30 m (98 ft)
l
Reduced diameter Microbore: 3 m (10 ft)
Note:
When the sampling hole is fitted with a metallic meshed plate an additional reducer connector is
required to transition from reduced diameter tube to normal tube. The normal tube length connecting
to the metallic sampling hole should be 0.1m (0.33ft).
To check for leakage use Xtralis VSC to set the VESDA VFT to sample from one port and follow the steps
below:
1. Connect a 50 m (164 ft) length normal tube and record detector Relative Pressure. This forms the
baseline pressure for comparison with the alternate tube configurations.
2. Record detector Relative Pressure for new tube configuration(s).
3. Difference between points 1 and 2 must be less than 3%. If above 3%, inspect to ensure tubes are
tightly fit to connector.
Before leakage testing, ensure that the VESDA VFT detector is in operation for at least 30 minutes.
