Lennox @DNOVA 2mAC ADVANCED CONTROLLER User manual

Providing indoor climate comfort
@DNOVA-µAC-IOM-0907-E
Installation,
operating and maintenance
@DNOVA
2µAC ADVANCED CONTROLLER

IOM / @DNOVA-µAC-0907-E - Page 1
CONTENTSCONTENTS
CONTENTS
GENERAL CHARACTERISTICS 2
General description ......................................................................................................2
µAC USER INTERFACE 2
The display...................................................................................................................3
Status indicators...........................................................................................................4
The keypad ..................................................................................................................4
INSTALLATION 4
Initial start-up procedure ..............................................................................................4
The I/O (Input/Output) board........................................................................................4
Meaning of the inputs and the outputs .........................................................................5
OPERATING MODES 6
Precision units for telecom ...........................................................................................6
Connecting a series of units.........................................................................................6
PROGRAMMING PARAMETERS AND THEIR MODIFICATION 7
Parameters...................................................................................................................7
Parameter modication ................................................................................................7
DESCRIPTION AND CONFIGURATION OF THE PARAMETERS 9
= probe parameters.................................................................................................12
r = regulation parameters...........................................................................................13
c= compressor management parameters ..................................................................16
F= fan management parameters................................................................................16
P= alarm management parameters ...........................................................................18
H= general conguration parameters.........................................................................19
Heating/cooling valve and damper management .................................................21
Condensation control............................................................................................21
Free-cooling function............................................................................................22
CLOCK, TIME BANDS AND ALARM LOG 23
Clock ..........................................................................................................................23
Time bands.................................................................................................................23
Alarm log ....................................................................................................................24
ALARMS AND SIGNALS 26
Table of alarms...........................................................................................................26
Alarm signals..............................................................................................................27
Machine shut-down signals........................................................................................28
OPTIONAL BOARDS 29
RS485 serial board ....................................................................................................29
Clock board ................................................................................................................29
TECHNICAL SPECIFICATIONS 30

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GENERAL CHARACTERISTICS
Controlled devices:
• 1 or 2 compressors or valve for cooling battery
• 1 or 2 heating elements or valve for heating battery
• Supply fan in ON-OFF or proportional mode
• Humidier with proportional or ON-OFF output
• Dehumidication with ON-OFF output
• Alarm device
Options:
• RS485 serial board
• Clock board with memory for logging the alarms and time
bands
• Programming key
Programming:
All the machine parameters can be configured not only
using the keypad located on the front panel, but also using a
hardware key and/or via serial line.
GENERAL CHARACTERISTICS
General description
The µAC is an electronic control for the complete management
of precision air-conditioners, for “Shelters” with management
of the condenser fan.
Main functions:
• Control based on the temperature and humidity of the inlet
air
• Energy saving with free-cooling (Shelters) or compensation
• Dehumidication management
• Control of the supply fan speed
• Complete alarm management with log
• Rotation of a series of units
• Time bands
• Can be connected to a serial line for supervisor /
telemaintenance

IOM / @DNOVA-µAC-0907-E - Page 3
µAC USER INTERFACE
programming phase
- password setting - parameter modication blocked
(in clock function) day of the week
clock display - clock set-up
ambient temperature in prog. displays the value of the parameter
temp. unit of measure: degrees Centigrade/Fahrenheit
ambient humidity in programming displays the no. of the parameter
relative humidity unit of measure
buzzer active
hour counter limit exceeded
OFF status from time bands
time bands active
external contact status:
- ON - machine enabled;
- OFF - machine in stand-by
indicates that the value displayed is the temperature (with this symbol off the Set-point is displayed)
time band selected
dehumidication active
ventilation active : % fan speed
cooling active: - number (1 or 2) cooling actuators; % opening cooling valve, or (in shelter mode) % opening free
cooling damper
heating active: - number (1 or 2 ) heating actuators - % opening valve
humidication active: % steam production
The display
The display shows the main measurements monitored and
the status of the machine and the actuators. Following is a
description of the symbols and the messages shown on the
display, and the corresponding meaning. Fig. 2 illustrates all
the symbols and the messages shown on the display; this
occurs on starting the regulator.
Fig. 2 Display
µAC USER INTERFACE
The µAC is made up of a display and a power board, installed
together in the same case, see Fig. 1.
Fig. 1 User interface
o

Page 4 - IOM / @DNOVA-µAC-0907-E
µAC USER INTERFACE
The buttons have the following meanings:
- Commutes status: if the machine is on, one press of the button places it in Standby; vice-versa, it is re-
enabled.
- Pressed for 5 secs accesses the User parameters.
- In the presence of an alarm silences the buzzer.
- Repeated pressing displays, cyclically: the current time, date and the temperature of the air in the room.
- In programming phase scrolls or increases the value of the parameters.
- Held pressed displays the set-point.
- In programming phase scrolls or decreases the value of the parameters.
- Pressed for 5 secs accesses the Direct parameters.
- In programming phase modies the value of the selected parameter.
- Pressed together for 5 secs access the Factory parameters.
- Pressed together for 2 secs reset the alarms.
Status indicators
The main states of the regulator (power supply present, alarm
active and remote ON/OFF input status) are displayed to the
user through 3 LEDs on the front panel.
Meaning of the LED
Line LED (yellow): control powered
Alarm LED (red): machine alarm (the siren symbol on the
display is on only when the buzzer is active)
ON LED (green): machine ON from keypad or supervisor
(referred to the EEPROM variable). The effective ON status of
the machine may, in addition, depend on the ON-OFF digital
input, on the active time band, the stand-by condition transmitted
from the master unit (if a series of units is in rotation), and is
indicated by the illumination of the fan symbol.
The ON-OFF symbols on the Display are illuminated only
when the input of the remote contact is enabled and
indicate the status of such contact.
The keypad
on/off
alarm
enter
+
enter
alarm
+

IOM / @DNOVA-µAC-0907-E - Page 5
INSTALLATION
The I/O (Input/Output) board
Fig. 3 shows the I/O board.
With reference to this gure, we can see:
- in the lower part the Molex connectors (1 - 2 - 3), for the
main connections;
- in the upper part, the 2nd male connector from the left, to
insert the key for programming the µAC or copy the existing
data;
- the tting for the clock board (optional);
- the tting for the RS485 serial board (optional);
- in the centre of the board, the jumper for selecting the hardware
of probe B3 (4÷20mA/ 0÷1Vdc), with default 0÷1Vdc.
Fig. 3
Digital inputs Connector 2
ID1 Remote ON/OFF (HE=1)
ID2 Flow controller
ID3 Filter dirty
ID4 Heat. Element safety
ID5 External alarm/ input for rotation of a series of
units rotation of a series of units (depends on
Pb-H2-HA)
ID6 No power alarm
ID7 High press.C1
ID8 Low press. C1
ID9 Comp. thermal
ID10 Fan thermal (H5)
Analogue inputs - Connector 2
B1 Inlet temp. Temp.
B2 External air temp. for free cooling (/1,Hc)
B3 Condens. press. (/2,Hd,Hb)
B4 Supply temp. (/3=1)
SSR digital outputs - Connector 1
Out1 Compressor
Out2 Heating element
Out3 Damper+(/2, Hc) Damper ON/OFF
Out4 Damper - (/2, Hc)
Out5 Supply fan
Relay digital outputs - Connector 3
Out 6 Alarm (HF)
Out 7 Alarm (HA) Rotation control (H2)
Analogue outputs - Connector 1
Y1 Damper output (/2,Hc)
Y2 Condensation fan (/1,/2,Hb,Hc)
key
Meaning of the inputs and the outputs
The following table (P. 6) describes the meaning of the inputs and the outputs according to the type of machine selected.
Telecom= precision unit complete with condenser and without humidier.
Inputs and outputs I/O
INSTALLATION
Initial start-up procedure
To install the control, proceed as indicated below, with
reference to the connection diagrams provided.
1. connect the probes and power supply: the probes can be
located up to a maximum distance of 50 metres from the
control, using cables with a minimum cross-section of 1mm2;
to improve immunity to disturbance it is recommended to use
shielded cables (connect one end only of the shield to the
ground on the electrical panel).
2. Program the instrument: for a more in-depth description
see chapter 5, “Programming”.
3. Connect the actuators: it is suggested to connect
connectors 1 and 3 only after having programmed the control.
On this subject, iavoid to connect loads exceeding the relay
rating.
clock opz. serial RS485 opz.
jumper B3 selection
0 + 1 Vdc
fuse 800 mAT

Page 6 - IOM / @DNOVA-µAC-0907-E
OPERATING MODES
Connecting a series of units
This conguration is possible both for direct expansion (ED)
and battery (CW) machines, as well as Shelter models. This
allows the timed rotation of a unit in stand-by within a group
of maximum 2 units. If one of the machines in operation
goes into an alarm condition, theunit in stand-by is activated.
Unit 1 Unit 2
LineLine
GO
Fig. 3 Connecting 2 units
This is done using a digital input and output which, via
the “master” (unit 1), sends the command to activate and
deactivate the unit in stand-by (the command is updated every
10 minutes).
Heating
element
Air outlet
Air inlet
Air ow
diverter
Condenser
air outlet
Condenser
side air inlet
Recirculation
fan
line line line line
condensator
fan
alarm alarm 1
No
damper
Power
supply
24Vac
main
fan
outdoor temp.
supply air temp.
room temp.
condensator pressure out
+ Vcc
air ow alarm
heaters alarm
power supply failure
low press. C1
fan overload
compr. overload
high press. C1
generic alarm
lter alarm
remote on/off
OPERATING MODES
Following are descriptions of some examples of the main machine congurations.
Precision units for telecom

IOM / @DNOVA-µAC-0907-E - Page 7
1. one (and only one) machine must be set as master;
2. it is recommended to terminate the line with a resistor (Rt),
value 220. 5W or 470. 4W.
3. check that G0 on the transformers is not earthed, to avoid
unwanted current at G0.
For operation, parameters H2, H3, H4, HA must be set (see
following parameter table and description).
PROGRAMMING PARAMETERS AND THEIR MODIFICATION
PROGRAMMING PARAMETERS AND THEIR MODIFICATION
Parameters
The parameters are divided into 3 levels, each of which
contains the previous, which the user can access to customise
the operation of the µAC.
N.B. It is not possible to move directly from one level
to another; the current programming phase must be
terminated before accessing the desired level (see
parameter HL).
Level Access
DIRECT (D): immediate access
USER (U): access via password 22 (parameter HH)
FACTORY (F): access via factory password 177
Parameter modication
Accessing Direct parameters (D)
The value of the rst accessible parameter is displayed in the
upper right, with the parameter code ashing.
Accessing User parameters (U)
The number 0 is displayed and, on the left the lock symbol ,
conrming access via password to the procedure.
- The and buttons are used to enter the password 22
(default), which is conrmed by pressing the
enter
button. The
value of the rst accessible parameter is then displayed in the
upper right, with the parameter code ashing.
5 Sec.
5 Sec.
The diagram shows how all the electrical panels can be the
same, and only during installation does connection have to
be made, as in Fig. 4, using a three-pole cable between one
precision unit and the next. During installation the following
three points must be kept in mind:

Page 8 - IOM / @DNOVA-µAC-0907-E
Accessing Factory parameters (F)
The number 0 is displayed and, on the left the lock symbol
, conrming access via password to the procedure.
- The and buttons are used to enter the password 177,
which is conrmed by pressing the
enter
button.
5 Sec.
The value of the rst accessible parameter is then displayed
in the upper right, with the parameter code ashing.
The and buttons can be used to scroll the various
parameters.
Once having entered any level of parameters, one pressing
of the button displays the value, ashing, of the parameter
selected, while the and buttons can be used to
modify such value.
Press
enter
again to temporarily store the new value. Then, using
the and buttons, scroll the parameters menu, repeating
the previous steps for each parameter to be modied. Press
the
alarm
button, on the other hand, to store the modications
made and exit programming. During all phases of setting
the parameters the open book symbol is displayed in the
lower left of the display; on the other hand, when setting the
password, a lock also appears, conrming the presence
of a “block”. The presence of the parameters in the various
families depends on the value of some of these:
1. presence of external air probe;
2. presence of humidity probe;
3. presence of supply air probe.
PROGRAMMING PARAMETERS AND THEIR MODIFICATION