McQuay 5RT90BR Montageanleitung Seite 41

G Demand Ventilation Control
- One technique to reduce energy consumption while maintain adequate air quality is demand controlled ventilation.
Instead of setting at a fi xed air replacement rate, carbon dioxide sensor (CO
dynamically, based on the emissions of actual building occupants.
- CO sensor is an optional component supplied in fi eld. Refer to the information below for the recommendation of CO
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sensor selection:
(i) Type: Duct-mounted type
(ii) Power input: 24 VDC, 50Hz
(iii) Operating temperature range: 0 ~ 52°C
(iv) Ambient temperature range: -15 ~ 52ºC
(v) Measuring range: 0 ~ 5000 PPM (depends on the application)
(vi) Output voltage: 2 ~ 10 VDC
(vii) Wire size: AWG18
(viii) Maximum allowable current: 7A
(ix) Compliance standards: To follow local and national regulations
- The economizer controller comes with a build-in software which is ready with the integration of CO
only in economizer mode. User is allowed to choose the diff erent threshold value selection via Dip switch 3. Refer to
hardware setting guideline provided in part (D) (v) under chapter "CONTROL OPERATION GUIDE" in this manual for CO
PPM level threshold value selection.
For example: To use a CO
needs to do the following steps:-
Step 1: Enable SW4 in the only Dip Switch in controller main board to ON position (default factory
setting is in OFF position).
Step 2: Enable panel parameter G6 (economizer control) in remote controller to '1' (ON) position (default
factory setting is in '0' (OFF) position).
Step 3: Ensure SW2 in Dip Switch 4 (Economizer controller board) is in OFF position (default factory
setting is in OFF position).
Step 4: Enable SW1 in Dip Switch 3 (Economizer controller board) to ON position (default factory setting
is in OFF position).
{ SW1 in Dip Switch 3 = 25%, by calculation means 25% of 5000 PPM or equivalent to 1250
PPM }.
- If the CO sensor is exposed to outdoor environment, cover the sensor with a splash proof (IPX4) box with screw as
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locking mechanism or similar method to prevent water from entering into the CO
contact with the sensor. The connection of CO
- Then, connect the wire from CO
wires on CO sensor. Connect the wires as below:
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System ground wire - connect to fi rst pole of terminal block
with label 'GND' .
+24VDC live wire - connect to second pole of terminal block
with label '+24V' .
Output/ feedback signal wire - connect to third pole of
(You may refer to sticker wiring diagram which is located on
the front cover of junction box.)
Wrong wiring connection may cause the malfunction on
CO sensor or economizer controller board or both. Tie the
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wires with releasable cable ties under the junction box.
sensor with measuring range from 0 ~ 5000 PPM with the threshold value at 1250PPM, user
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sensor is considered a LIVE part.
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sensor to the junction box in the indoor compartment of the unit. There are three
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terminal block with label 'FB' .
CAUTION
Junction
box
sensor) is used to control the rate
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sensor and also to avoid possible
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TO PCB3 (ECO) TO PCB3 (ECO) TO PCB3 (ECO)
CN_ACT_RA CN_ACT_OA
TB RA TB OA TB C02
GND +24V DCV FB GND +24V DCV FB GND +24V
ACTUATOR RA ACTUATOR OA
Label 'RA'
Terminal block with label 'CO
connected with CO
Detail view of junction box
sensor. It is activated
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CN_C02
Sticker wiring
FB
diagram on
the front cover
of junction
box
C02 SENSOR
Label 'OA' Label 'CO '
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' - to be
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sensor.
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