110013961AA
date of change: 18.08.2008
page: 4/19
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22
2
General description of the control unit
General description of the control unit
General description of the control unit
General description of the control unit
Model FR4
FR4
FR4
FR4 is an electronical control unit (78x35mm) suitable for applications on medium or low tempera-
ture refrigeration units, which has three relay outputs to control compressor, defrost and evaporator
blower as well as two PTC-/NTC-sensor-inputs in order to measure the room temperature and evapora-
tor temperature. Defrosting can be recirculation air as well as hot-gas defrosting. The blower can be acti-
vated during defrosting upon request. The sensor is suitable for refrigeration. The control unit FR4 is suit-
able for refrigeration as well as heating applications (only hot-gas heating). Supply voltage may be between
10 and 28V.
The following functions can be adjusted:
•
room temperature („only refrigeration“ or „refrigeration and heating with hot gas “)
•
automatic defrosting (hot gas or recirculating air)
•
manual defrosting (hot gas or recirculating air)
⇒
Faults are shown in the display via flashing indication (see point 4).
This present instructions for installation and service is amended by the „operating
instructions for refrigeration units“, KONVEKTA no:
BBA-FR4-2AA
.
2.1
LED-display
The display shows information about the current control mode via different LED.
The functions are listed as follows:
LED
LED
LED
LED
STATUS
STATUS
STATUS
STATUS
FUN
FUN
FUN
FUNCT
CT
CT
CTION
ION
ION
ION
Comp illuminated
compressor is active
Comp
blinking
minimum off-duration of compressor is active
Fan
illuminated
Blowers active
Def
illuminated
defrosting active
Def
blinking
Manual defrosting active
OK
illuminated
function OK, no fault active
2.2
Programming Menu
The programming menu includes all parameters of the unit
(Service
(Service
(Service
(Service level
level
level
level!).
!).
!).
!). For this level you need a
password
, see example in point 5.1.
