Flame Signal Measurements; Siemens Lal Control Sequence Of Operations - Riello RL 70/M Installation, Use And Maintenance Instructions

(A)
(B)
(C)
LAL2... Sub-base
Full modulation
High - low
FLAME SIGNAL MEASUREMENT (A)
Min value for a good signal: 8 μA.
If the value is lower, it can be due to:
• Worn photocell;
• Low current;
• Bad set up of the burner.
In order to measure the current, use a microammeter of
100 μA c.c., connected to the scanner, as in the dia-
gram.
Min. detector current required at AC 230 V
Max. detector current required without
flame
Max. detector current that can occur
Instrument's + pole
D3206
Length of detector line
In the same cable as the control lines
Separate cable in the cable duct
Three-wire cable
Two-wire cable for the detector line (bl,
sw); separate single-wire cable for the line
(br)
Shielded cable (e.g. RG62, shielding insu-
lated)
Shielding
SEQUENCE OF OPERATION - LAL CONTROL
See fig. (B) - (C).
Switching times are given in seconds, in the burner star-
tup sequence.
LAL 2.25
t1
t2
t3
t4
Legend for the times
t1
t2
t3
t4
D2871
t5
t6
t7
t8
D2883
16
18 t5
4 t6
2 t7
12 t8
Pre-purge time with air damper open
Safety time
Pre-ignition time, short ("Z"
terminal "16")
Interval between voltage at terminals "18" and
"20"
Air damper running time to OPEN position
Air damper running time to low-flame position
(MIN)
Permissible after-burn time
Interval to the OPEN command for the air damper
8 μA
0.8 μA
35 μA
to term. 22
not perm.
20 m
---
---
200 m
to term. 23
optional
optional
12
4
connected to