Error Tree Analysis; Flame Detection - Westinghouse WGRT 150 Series Installation Start-Up Maintenance Parts

5. Cascade Transition – Down Transition
Transition
Over Capacity
5 to MAX 100%
5 32%
4-5
40%
4 32%
3-4 43%
3
32%
2-3 48%
2 32%
1-2 64%
1
Table 32 – Cascade Down Transition - ! Four units split the previous load in fourth, # Three units split the previous load in
third, @ Two units split the previous load in half, *The last unit takes the previous load
NOTE: If the amount of heat needed to reach 20 – 30% of the total load is needed, one of the units turns OFF.
K. ERROR TREE ANALYSIS

1. FLAME DETECTION

Figure 51 – Flame Detection Error Analysis Tree
1 2
The control valve reduces the flow when the load is over 80% of the total capacity.
100%
32%
40%
32%
43%
32%
48%
32%
*
0%
3 4
100% 100%
32% 32%
40% 40%
32% 32%
43% @
32%
#
5 -
100%
32%
!
WHL-004 REV. 5.26.17
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