Setting instructions
|
5
6 720 802 836 (2012/05)
CFB 840
2.3
Notes on commissioning
B
Before switching the control unit on, check that its manual switches
and those on the function modules are set to
AUT
.
B
Enter the settings made during commissioning and the allocation of
the heating circuits into the commissioning report in the operating
instructions of the control unit.
B
Switch on the control unit first and then the boiler.
B
To shut down, switch off the boiler first and then the control unit.
B
Ensure that there is sufficient heat load, otherwise the boiler will
switch off and generate a fault condition.
2.4
Cleaning the control unit
B
Only clean the control unit with a damp cloth.
2.5
Product description
The digital CFB 840 control unit is suitable for regulating a floor-standing
oil/gas-fired boiler with single stage, two-stage or modulating burner.
As standard, the unit includes the DHW heating (cylinder system) and
heating circuit control (one heating circuit without actuator) functions. It
can be expanded by adding up to two function modules to suit the
requirements of the heating system.
2.6
Scope of supply
Included in the standard delivery:
•
Digital CFB 840 control unit with programming unit
•
FA outside temperature sensor
•
Boiler water temperature sensor FK
2.7
Technical data
2.7.1 Controller CFB 840
2.7.2 FM442/CMM 920 function module
3
Setting instructions
3.1
Setting instructions and replacement instructions for
high limit safety cut-out (STB)
3.1.1 Setting and installation of the high limit safety cut-out
To be able to set the temperatures, the high limit safety cut-out (STB)
must be removed from the control unit housing.
B
Undo screws [1].
B
Remove cover [2].
B
Remove protective cap [3].
B
Undo the screw connection.
B
Remove the STB with its assembly plate and make the adjustments
(
Æ
chapter 3.1.2).
DANGER:
Risk to life and of system damage through
excessively high temperatures.
All parts directly or indirectly subject to high
temperatures must be designed for use at such
temperatures.
B
Ensure that wiring and other lines are routed at a safe
distance from hot boiler parts.
B
Route wiring and other lines, in the wiring ducts
provided or above the boiler insulation.
Unit
CFB 840
Dimensions B/H/L
mm
460/240/230
Operating voltage (at 50 Hz ±4 %)
V
230
±
10 %
Power consumption
VA
5
Control unit fuse
A
10
Maximum switching current
•
Burner output
•
Boiler or heating circuit pump
output
A
8
5
Boiler circuit actuator control
V
230
Servomotor runtime, burner
modulating
sec
120
(adjustable from 5 to
60)
Type of controller - burner and
heating circuit actuator
Three-point stepper
controller (PI
characteristics)
Ambient temperatures
•
Operation
•
Transport
°C
+5...+50
–20...+55
Table 2 Specification - CFB 840 control unit
Sensor
lower fault
limit in °C
smallest
display value
in °C
highest
display value
in °C
upper fault
limit in °C
FA
–50
–40
50
> 70
FK
< –5
0
> 108
> 125
FB
< –5
0
99
> 125
Table 3 Sensor measuring range
Unit
Value
Operating voltage (at 50 Hz
±
4 %)
V
230
±
10 %
Power consumption
VA
2
Maximum switching current - heating
circuit circulation pump output
A
5
Heating circuit actuator control
V
230
Servomotor runtime
sec
120 (adjustable
10 – 600)
Type of controller
–
Three-point stepper
controller (PI
characteristics)
Table 4 Technical data for FM442/CMM 920 function module
Sensor
lower
fault
limit
in °C
smallest
display
value
in °C
highest
display
value
in °C
upper fault limit
in °C
FV1 flow temp. HC
on left
< –5
0
99
125
FB flow temp. HC
on right
< –5
0
99
125
Table 5 Sensor measuring range
DANGER:
Risk to life from electric shock!
B
Before opening the control unit, isolate all poles of the
control unit and secure against unauthorised re-
connection.
