3D Connexion mD4000-b Manuel D’Utilisation

Manual 2100-574

Page 

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•Input power: 18-32 VAC, 60/50Hz, power is supplied from 
A/C #1 and/or A/C #2

•Isolation circuitry: no line or low voltage phasing required

•Backup power: connection for -24 VDC or -48 VDC (-20 to 
-56V) maintains microprocessor operation, front panel indication 
& alarm relay operation during commercial power outages.

•Digital display: 4-character LCD

•Temperature display: F or C

•HVAC outputs: Form A (NO) relays (1A @ 24 VAC)

•Cooling control stages:

  2 for each A/C unit (4 total)

•Heating Control stages:

  1 for each A/C unit

•Operating temperature range: 0 to 120F (-18 to 49C)

•Storage temperature range: -20 to 140F (-29 to 60C)

•Temperature accuracy:  +/- 1F from 60-85F (16-30C)

 

+/- 1% outside 60-85F

•Lead/lag changeover time: 0 to 30 days

•Timing accuracy: +/- 1%

•Inter-stage time delay: 10 seconds between stages

•On-Off differential: 2F (1C) is standard, 4F (3C) when 
“excessive cycling” mode is enabled

•Comfort setting, Heating 68F(20C), for 1 hour

•Dead band (difference between cooling and heating set 
points): 2F to 40F (1.1C to 22.2C)

•Fire/smoke interface: standard NC circuit jumper, remove 
for connection to building system control, shuts down both 
A/C units immediately   

•Memory: EEPROM for set point and changeable 
parameters (maintains settings on power loss)

•Space temperature sensors: 1 local is standard, will accept up 
to 2 optional 25' remote sensors, Bard part number 8612-023.  
When multiple sensors are used, temperatures are averaged

•Controller Enclosure: 20-gauge pre-painted steel, 9.25"W 

x 20.875"H x 3.00"D, hinged cover, twenty four (24) .875" 
diameter electrical knockouts

•LEDs for basic controller: Lead unit, Heating Stages 1 – 4

•Six (6) Push-button controls: On/Off switch-Change lead 
unit-Increase & Decrease set points-Program/Save-Comfort.

Included in the controller carton is the controller and 
installation instructions.
The controller should be installed on a vertical wall 

approximately four (4) feet above the floor-away from drafts & 
outside doors or windows.  Four (4) mounting holes are provided 

for mounting to the wall and 7/8" holes for conduit connections 
are provided in both the base, sides &  top of the controller.

The standard (local) temperature sensor has 12" leads and 
comes installed from the factory.
A secondary sensor is located internally on the main 
controller board and serves as a reference and back-up 

sensor to the local sensor.  Any differential of +/- 12F 
between the on-board and local sensor will cause the 
controller to use the local sensor as its point of reference.  

If the differential is greater than 12F then the controller 
will check to determine the on-board sensor is reading a 
temperature that is between the SP (set-point) plus 12F 
and the SP minus the DB (dead-band) minus 12F.  If it is 
the on-board sensor will become the valid sensor reading 
and the controller will ignore the local sensor reading.  If 
it is not then the controller will still use the local sensor 
reading.  This is to add additional level of operational 
capability in the rare event the local sensor fails.  If the 
controller is operating in this mode it is indicated by the 

lower left decimal point flashing in the display.  Note: for 
purposes of testing when the local sensor is manually 
driven higher or lower by applying warm or cool water 

to the probe the on-board sensor is inhibited for the first 
30-minutes following power up, or when power is cycled 
off and back on.
The controller is designed to accept 1 or 2 additional 
sensors and those have 25-foot leads.  The Bard part 
number for the optional sensor with 25-foot leads is 
8612-023.  These can be installed as required in the 

structure to address hot spots, barriers to airflow, etc.
It is recommended that the sensor lead wires be installed 
in conduit for protective purposes.
The highest reading of any connected sensor will be 
used for high temperature alarm and the lowest reading 
sensor will be used for low temperature alarm.

The standard local (LSEn) sensor monitors the 
temperature at the controller location.  If this is the only 
sensor connected, it will control the temperature read-out, 
the space (building) temperature, and also be used for 
Low and High Temperature alarm functions.
If one or more REMOtE sensors are installed and 
connected (Rem 1 or Rem 2), the temperature read-out 
will display and the building will be controlled to an 
average of all connected sensors.  If there is more than 
10F difference from the highest to the lowest connected 
sensor, the actual control will be governed by the hottest 
sensor for cooling and the coldest sensor for heating.
If multiple temperature sensors are used, the High and 
Low temperature alarms will be governed by the average 
of the connected sensors. 

Note: All sensors are polarity sensitive.  the copper 
lead must connect to terminal CU, and the silver 
lead to AG.  Sensors are solid state, not RtD.  Use 
only sensors supplied by Bard.  Sensor leads can be 
extended up to 200 feet.  Use 18-gauge twisted pair 
with soldered connections.