Zanotti un0 010, Workshop Manual

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Electronics and wiring
5.8 Running logic
Automatic Cooling Mode Operation Sequence
When running in Automatic Mode, unit stops operations every time cold-room reaches SP set-point temperature, waiting that
difference between TA actual and SP set-point temperatures exceeds dF differential to restart with required operations.
1 ON Signal.
1(’)-2 Starting Procedure.
2-3 Cooling Operations.
3 TA Cold-room temperature has
reached SP set-point value.
3-1’ Unit Stand-by, waiting for
cooling/heating request.
1’ TA Cold-room temperature is out
from admitted range (SP±dF).
4 OFF Signal.
Continuous Cooling Mode Operation Sequence
1 ON Signal.
1-2 Starting Procedure.
2-3 High Speed Pull Down.
3 TA-SP<ddF Engine decreases speed.
3-4 Unit Cools cold-room at Slow speed.
4 Unit starts to heat.
4-5 Unit Heats at Slow speed.
5 Unit starts to Cool.
5-4 Unit Cools at Slow speed.
2’ TA-SP>ddF Engine increases speed.
2’-3 High Speed Cooling.
6 Heating unit increases speed.
6-7 High Speed Heating.
7 Unit decreases speed.
7-5 Unit Heats at Slow speed.
8 OFF Signal.