Specifications Continued - Siemens LFL Series Technical Instructions

Specifications continued...

Voltage – during burner operation
Flame
Voltage – during start-up phase (flame circuit check)
supervision
Required minimum UV sensor signal
with
Typical UV sensor signal measurement
UV sensor
QRA... Length of detector cable (run in a separate conduit from all other wiring)
- Unshielded wire
- Shielded cable, shield grounded to terminal 22
Voltage at the flame rod – during burner operation
Flame
Voltage at the flame rod – during start-up phase (flame circuit check)
supervision
Required minimum flame rod signal
with
Typical flame signal measurement
Flame rod
Short-circuit current
Length of detector cable (run in a separate conduit from all other wiring)
- Unshielded wire
- Shielded cable, shield grounded to terminal 22
Electrical connection notes for flame supervision
Siemens Building Technologies
HVAC Products
• It is important to minimize electrical disturbance and signal loss.
• Run flame signal wiring separate from all other wiring
• Observe the length of detector cable as indicated above
• The flame rod does not provide protection from electric shock
• Locate the ignition electrode(s) and flame rod such that the ignition spark cannot arc to the
flame rod (risk of electrical overload and damage to flame supervision circuit)
• When using the QRA..., grounding of terminal 22 is required
• Multiple UV sensors QRA... and/or flame rods can be connected in parallel
• If separate flame sensors are used for pilot and main flame supervision,
an interrupted pilot must be utilized
330 Vac ±10 %
380 Vac ±10 %
70 µA
100-450 µA
max. 300 ft
max. 600 ft
330 Vac ±10 %
380 Vac ±10 %
6 µA
20-100 µA
max. 0.5 mA
max. 250 ft
max. 500 ft
5/12
CC1N7451en
11.15.2004