Daikin MicroTech III Operation Manuals page 103

Minimum Outside Air Reset - None
If None is selected as the Min OA Reset Type, the Minimum
OA Position is set equal to the Ventilation Limit . The Demand
Control Ventilation Limit value is ignored when Min OA reset is
set to None .
Minimum Outside Air Reset - Network Control
If Network is selected as the Min OA Reset Type and a valid
value for the minimum position is provided via a network the
Minimum OA Position is set equal to that value . The network
is only allowed to write a value that is between the Ventilation
Limit and the Demand Control Ventilation Limit current values .
If Network is selected as the Min OA Reset Type and a valid
value for the minimum position is not provided, the Min OA
position is set equal to the Ventilation Limit .
Minimum Outside Air Reset - External Control
If ExtV is selected as the Min OA Reset Type, the Minimum OA
Position is calculated based on an external 0-10 VDC signal .
If ExtmA is selected as the Min OA Type, the Minimum OA
Position is calculated based on an external 0-20 mA signal .
This calculated Minimum OA Position varies linearly from zero
% at the editable minimum external signal to the maximum
value at the editable maximum external signal, but it is set no
lower than the Demand Control Ventilation Limit and no higher
than the Ventilation Limit .
Minimum Outside Air Reset -IAQ
If either IAQV or IAQ mA is selected as the Min OA Type,
the Minimum OA Position is calculated based on a 0-10V or
0-20 mA CO sensor input . The CO
2
Parts Per Million . The minimum and maximum sensor input
values (0-10V or 0-20 mA) and the corresponding minimum
and maximum PPM values are user defined. This calculated
Minimum OA Position varies linearly from the Demand Control
Ventilation Limit at the "PPM @ DCV Limit" to the Ventilation
Limit at the "PPM @ VentLimit"" . The "PPM @ DCV Limit"
is not allow to be set equal to or greater than the "PPM @
VentLimit"
Examples of typical Min OA reset schedules .
If IAQ VDC is selected as the Min OA Type, the Minimum OA
Position is calculated based on a 0-10V CO
The CO level is expressed as PPM (Parts Per Million) . The
2
minimum and maximum sensor input values (0-10V) and the
corresponding minimum and maximum PPM values are user
changeable . This calculated Minimum OA Position varies
linearly from the Demand Control Ventilation Limit at the value
labeled "PPM @ DCV Limit" to the Ventilation Limit at the value
labeled "PPM @ VentLimit" . The "PPM @ DCV Limit" is not
allow to be set equal to or greater than the "PPM @ VentLimit"
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level is expressed as
2
sensor input .
2
103
Example #1 Min OA reset type = IAQ VDC
If the requirement is to have the OA damper be at its minimum
(Demand Control Ventilation Limit) when the CO
less than 800 PPM and to be at its maximum (Ventilation Limit)
when the CO levels are greater than 1000 PPM, the controller
2
would be set up as follow:
• Vent Limit = 100%
• Lo Flow Vent Limit = 100%
• DCV Limit = 0%
• Min OA reset type = IAQ VDC
• PPM@DCV Limit = 800
• PPM@Vent Limit = 1000
• IAQ PPM = Current PPM
• Min PPM = 0 (From CO
• Max PPM = 2000 (From CO
• V/A @ Min PPM = 0 VDC
• V/A @ Max PPM = 10 VDC
In this example the Minimum OA Position would vary linearly
from 0% outside air at 800 PPM or less to 100% outside air at
1000 PPM or greater .
Examples of typical Min OA reset schedules .
If EXT VDC is selected as the Min OA Type, the Minimum OA
Position is calculated based on an external 0-10 VDC signal .
This calculated Minimum OA Position varies linearly from zero
% at the changeable minimum external signal to 100% at the
changeable maximum external signal, but it is set no lower
than the Demand Control Ventilation Limit and no higher than
the Ventilation Limit .
Example #2 Min OA reset type = EXT VDC
If the requirement is to have the OA damper be at its minimum
(Demand Control Ventilation Limit) when the field supplied
signal is at its minimum (0 VDC) and to be at its maximum
(Ventilation Limit) when the field supplied signal is at its
maximum (10 VDC), the controller would be set up as follow:
• Vent Limit = 100%
• Lo Flow Vent Limit = 100%
• DCV Limit = 10%
• Min OA reset type = EXT VDC
• OA@MinV/mA = 0%
• OA@MaxV/mA = 100%
• Min V/mA = 0 VDC
• Max V/mA = 10 VDC
In this example the Minimum OA Position would vary linearly
from 0% outside air at 0 VDC to 100% outside air at 10 VDC .
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