Zanotti un0 060, Workshop Manual

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5.3 Digital Sensors
Electronics and wiring
5.3 Digital Sensors
Digital sensors give binary signals to CPU board which elaborating info, according programmed logic, manages all unit
devices. Binary signals O or 1 represents a contact state Opened or Closed, all of these sensor are just working as switches,
opening and closing their contact according pressure, temperature or other specific sensing conditions. Each of which can be
Enabled or Disabled from Digital Input Management menu.
SA Differential Air Switch
Specifications:
Circuit unipolar
State N.O.
Opens at < 2.4mbar)
Closes at > 2.4mbar (0.035psi)
Connections:
Port-Pin by Wire
J10 − 2
nd
NE102
J8 − 1
st
75
Functions:
Differential air switch SA detects evaporator ice presence
checking air flow pressure difference.
Digital Input menu label:
Differential pressure switch
FTQ Water Temperature Switch
Specifications:
Circuit unipolar Absorption 3W State N.O.
Closes at 107 − 113[°C] (225 − 235[°F ])
Reopen at 80 − 85[°C] (176 − 185[°F ])
Connections:
Port-Pin by Wire
J10 − 4
th
NE104
J8 − 8
th
13
Functions:
This sensor stops the unit with A07 alarm when detected
coolant temperature exceeds set value to prevent
overheating.
CAUTION! ! In case of sensor disconnection, unit works
normally and in case of overheating no protection engages.