Unigas PBY1025 Manual Of Installation - Use - Maintenance page 43

Sequence diagram
A
t11
a
I
b
t7
a
II
b
a
III
b
IV
a
V
b
t1 6
V I
a
V II
b
a
V III
b
IX
a
X
b
a
X I
b
a
X II *
b
t10*
a
X III
b
a
X IV
b
Lockout position indication
Key
t1 Prepurge time with air damper fully open
t2 Safety time
t3 Preignition time, short («Z» connected to terminal 16)
T3' Preignition time, long («Z» connected to terminal 15)
t3n Postignition time («Z» connected to terminal 15)
t4 Interval between voltage at terminals 18 and 19 («BV1-BV2»)
t5 Interval between voltage at terminals 19 and 20 («BV2» load
controller)
t6 Postpurge time (with «M2»)
t7 Interval between start command and voltage at terminal 7 (start
delay time for «M2»)
t8 Duration of startup sequence (excluding «t11» and «t12»)
t10 Interval from startup to the beginning of the air pressure check
t11 Air damper running time to the OPEN position
t12 Air damper running time to the low-fire position (MIN)
t13 Permissible afterburn time
t16 Interval to the OPEN command for the air damper
t20 For self-shutdown of the sequence switch
t1 t12
t3
t3"
t8
B C
t4
t3 n
t5
t20
t2
Control output at terminal
D
t6
*
4 1 2
7
1 9
16
10
9
15
9
11
20
8
17
1 8
t13