Stulz C2020 User Manual

EN/07.2013/58/58
If in the system there are only three units, the offset will be: Offset = S03 / 3 = S03 / M04
4.8.8. Dehumidification with humidity switch
If there isn’t the humidity probe and the humidity switch is present, the dehumidification function is under the control of
the humidity switch.
The parameters involved are:
• M04 MAX NUMBER OF UNITS ON: pre-set = 1
• M75 START DELAY SLAVE UNITS FOR DEHUMID: pre-set = 300sec
If the humidity switch is off, the system doesn’t do any action of dehumidification.
When the humidity switch of the leader is on, the evaporator fans will be immediately driven at their min speed and, after
a period of time equal to M75, the compressor of the unit off will be switched on. If after another interval time (M75), the
humidity switch is still on, another compressor will be switched on. The number of compressors on will be limited by the
parameter M04. When the Humidity switch turns off, all compressors will be switched off.
4.8.9. Dehumidification with humidity probe
If the humidity probe is present, the dehumidification function will be under the control of it.
The parameters involved are:
• M04 MAX NUMBER OF UNIT ON: pre-set = 1
• M75 START DELAY SLAVE UNITS FOR DEHUMID: pre-set = 300sec
To dehumidify, the leader board has to met the conditions shown in par. 4.2.
If the leader board is dehumidifying and the period of time M75 is elapsed, an unit of support will start to dehumidify. If
after another interval time (M75) the dehumidification required conditions are still there, another support unit will start to
dehumidify. The number of unit on is limited by the parameter M04.
When the dehumidification condition is over (according to par. 5.2) all compressors will be switched off.
4.8.10. Humidification
The parameters involved are:
• S05 HUMIDITY SET POINT: pre-set = 40%
• S08 HUMIDITY BAND: pre-set = 50%
• M03 NUMBER OF PRESENT UNITS: pre-set = 1
• M77 HUMIDIFICATION ENABLE: pre-set = NO
• M78 HUMIDIFICATION MODE: pre-set = 0 (Digital humidifier)
• M79 HUMIDIFICATION START: pre-set = 20%
• M80 HUMIDIFICATION STOP: pre-set = 2%
Set the parameter M77 to YES to enable the humidification in sequencing mode.
If the leader unit is not sufficient to humidify, it will ask support to the units with the lower number of evaporator fan
running hours. The logic function is under control of the master unit.
For example, in a system of five units the behaviour of digital humidifier (M78 set to 0) is as follows:
Humidifier starts to humidify when: Humidifier stops to humidify when:
Unit 1 (Leader board)
IRH
ON
=S05-(M80*S08)/100–UNIT_OFFSET IRH
OFF
=S05-(M80*S08)/100
Unit 2
IRH
ON
=S05-(M80*S08)/100–(2*UNIT_OFFSET) IRH
OFF
=S05-(M80*S08)/100–UNIT_OFFSET
Unit 3
IRH
ON
=S05-(M80*S08)/100–(3*UNIT_OFFSET) IRH
OFF
=S05-(M80*S08)/100–(2*UNIT_OFFSET)
Unit 4
IRH
ON
=S055-(M80*S08)/100–(4*UNIT_OFFSET) IRH
OFF
=S05-(M80*S08)/100–(3*UNIT_OFFSET)
Unit 5
IRH
ON
=S05-(M80*S08)/100–(5*UNIT_OFFSET) IRH
OFF
=S05-(M80*S08)/100–(4*UNIT_OFFSET)
Where: UNIT_OFFSET = ((M79 – M80) * S08) / (M03 * 100)

Stulz C2020 Specifications

General

Brand	Stulz
Model	C2020
Category	Controller
Language	English