72
8
Options
8.6.1
Functional Description
Properties:
•
Two Pt100 temperature inputs to record the flue gas temperature and inlet temperature
•
Two analogue outputs 0/4
...
20
mA to emit the flue gas temperature and efficiency
•
Power supply 24
VDC/50
mA
(PELV)
NOTICE
All outgoing lines from the LSB module must be screened. The screens must be applied to the
PE rail as short as possible.
Description of function
The calculation takes place according to the following formula:
n
F
= 100 (q
Af
+ q
Ag
) %
q
Af
= flue gas loss due to free heat
q
Ag
= flue gas loss due to bound heat
q
Af
= ( t
A
- t
L
) * [A
2
/ 21 – O
2
+ B]
The calculation of the flue gas losses is based on the following mean fuel values:
Oil A
2
= 0.68; B = 0.007
Gas A
2
= 0.66; B = 0.009
It is assumed that the combustion takes place free of CO and soot. The flue gas losses due
to bound heat q
Ag
are not taken into consideration.
Function not effective until < 14.9 vol.
%
O
2
.
Display:
NOTICE
In case of overflow/underflow of the measuring range, the corresponding measured values
flash.
NOTICE
The termination resistor (120
)
must
be installed and activated on the first and the last BUS
device.
Avoid transmission line!
The terminal resistance can be set via DIP switch 1.
ETA
efficiency 0
...
100%
T-ex
flue gas temperature 0
...
400
°C
T air
inlet air temperature 0
...
400
°C
Summary of Contents for LT3
Page 2: ......
Page 14: ...13 3 Product Description 3 2 C Declaration of Conformity...
Page 15: ...14 3 Product Description...
Page 19: ...18 4 Display and Operational Controls 4 2 4 Settings Menu Structure...
Page 22: ...21 4 Display and Operational Controls 4 4 1 Main Menu Password Entry...
Page 79: ...78 11 Appendix...