VDH MC 785-DF KLIMA Operating Manual

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MC 785-DF KLIMA

ALFANET implementation

Operating Manual

(Wall and panel mounting)

Description : MC 785-DF KLIMA ALFANET (RS485) Thermo/hygrostat Doc.nr.: 010346

Type: MANUAL Number of pages: 20 Version: V1.4

File: Do010346 MC785-DF KLIMA Alfanet v14 EN.wpd Software: 010187 MC 785 DF Kli Alfanet

Version: V1.03

By: BJB Date: 15-02-2018

VDH Products BV - Roden - Holland Signed: File: Doc'01

Operating manual Document nr. : 010346 Version : V1.4

MC 785-DF KLIMA ALFANET Client : General Page : 2 of 20

Table of contents

1. Technical specifications. ........................................................... 3

1.1 Controller General .......................................................... 3

1.2 LMS Relay module .......................................................... 4

1.3 LMS 4x Pt100 module ....................................................... 4

1.4 LMS Analog-out module ...................................................... 4

1.5 LMS Supply module ......................................................... 4

2. Functional specifications. .......................................................... 5

3. Control. ........................................................................ 6

3.1 Readout (lowest) defrost temperature and seperate sensors. .......................... 6

3.2 Changing the temperature setpoint. ............................................. 6

3.3 Changing of the RH setpoint. .................................................. 6

3.4 Resetting the alarm. ......................................................... 6

3.5 Day/night input. ............................................................ 6

3.6 Manual start of defrost. ....................................................... 7

3.7 Operation of fan control. ...................................................... 7

3.8 Readout output percentages of the analog outputs CH-1 untill CH-4. .................... 7

4. Programming internal settings. ...................................................... 8

4.1 Parameter table ............................................................ 8

5. Operation of the relay outputs. ......................................................13

5.1 Operation of the cooling and heating. ............................................13

5.2 Operation of the humidification and dehumidification ................................13

5.3 Operation of defrost. ........................................................13

6. Sensor calibration. ...............................................................14

7. Alarms. ........................................................................14

8. Front view. .....................................................................15

9. Connection diagram. ..............................................................16

10. Dimensions. ....................................................................19

The information in this document is assumed to be accurate. However VDH Products B.V. accepts no liability for eventual m istakes or errors and has the right to change this docum ent without notice.

Operating manual Document nr. : 010346 Version : V1.4

MC 785-DF KLIMA ALFANET Client : General Page : 3 of 20

1. Technical specifications.

1.1 Controller General Type : MC 785-DF KLIMA ALFANET Wall mounting:

Housing : Grey plastic Material : Polystyrol 454h KG 2 natur BASF Dimensions : 213 x 180 x 85mm (whd) Front : Polycarbonat

Panel mounting:

Housing : Steel plate panel Material : Steel in silver grey Dimensions : 217 x 155 x 85mm (whd) Panel cutout : min. 208 x 146mm (wh) Front : Polycarbonat

Temperature range : -40/+50EC per 0,1EC Humidity range : 0/+100% RH per 0,1% RH Supply : 230 Vac; 50/60 Hz (-10/+5%). Used power : 9 VA Operation temperature : Max. 40EC

Controller Front Display : 4-digit digital display for measured temperature

4-digit digital display for temperature setpoint 4-digit digital display for measured RH 4-digit digital display for RH setpoint

LED's : COOL = LED Relay cooling active

HEAT = LED Relay heating active DEHUM = LeD Relay dehumidification active HUM = LED Relay humidification active

= LED Alarm active (flashing)

= LED Day mode active

= LED Night mode active

= LED Fan active

= LED Defrost active

= LED Fan in auto mode

= LED Fan in manual mode (hand)

Keys : ON/OFF = On/Off key controller

SET = Setpoint push button

> = Up key ? = Down key

PRG = Program key RESET ALARM = Alarm reset key FAN = Fan auto/manual key DEFR START = Start defrost key DEFR SENS = Read-out defrost sensor key

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Controller in- and outputs Sensors : Temperature sensor (Pt-100, 3-wire to DIN/IEC 751)

Defrost sensor (Pt-100, 3-wire to DIN/IEC 751)

RH sensor (0/+1 Vdc = 0/+100% RH) Digital input : Day/night input (potential free input contact) Analog output : Out-1=CH-1; 0/+10Vdc, (Rbmin 10Kohm, programmable) Relay outputs : RY1 Extra relay (C/NO/NC, 250Vac/10A not inductive)

Following relays have a central common; RY2 Dehumidify (NO, 250Vac/10A not inductive) RY3 Humidify (NO, 250Vac/10A not inductive) RY4 Heating (NO, 250Vac/10A not inductive) RY5 Cooling (NO/NC, 250Vac/10A not inductive)

Please note ! Relay functions are programmable. These are the default settings.

Communcation : I²C network

(2-wire shielded; 0V,SDA,SCL)

RS485 network

according to NORM: ANSI/TIA/EIA-485-A-98

(2x Twisted-pair shielded, min. 0,5mm2; GND,A,B)

1.2 LMS Relay module Supply : 12Vdc / 1,2VA (from separate supply) Communication : I2C network

(2-wire shielded 0V,SDA,SCL)

Relay outputs : RY1 Defrost (C/NO/NC, 250Vac/10A not inductive)

RY2 Fan (C/NO, 250Vac/10A not inductive) RY3 Spare (C/NO, 250Vac/10A not inductive) RY4 Spare (C/NO, 250Vac/10A not inductive)

Please note ! Relay functions are programmable. These are the default settings.

1.3 LMS 4x Pt100 module Supply : 12Vdc / 1,2VA Communication : I2C network

(2-wire shielded 0V,SDA,SCL)

Sensors : Pt100-1 (3-wire according to DIN/IEC 751, programmable)

Pt100-2 (3-wire according to DIN/IEC 751, programmable) Pt100-3 (3-wire according to DIN/IEC 751, programmable) Pt100-4 (3-wire according to DIN/IEC 751, programmable)

1.4 LMS Analog-out module Supply : 12Vdc / 1,1VA (from separate supply) Communication : I2C network

(2-wire shielded 0V,SDA,SCL)

Analog outputs : Out-1=CH-2; 0/+10Vdc (Rbmin 10Kohm, programmable)

Out-2=CH-3; 0/+10Vdc (Rbmin 10Kohm, programmable) Out-3=CH-4; 0/+10Vdc (Rbmin 10Kohm, programmable) Out-4=CH-5; 0/+10Vdc (Rbmin 10Kohm, highest output percentage

Please note ! Analog functions are programmable. of CH-1 and CH-2)

1.5 LMS Supply module Supply : 230Vac 50/60Hz, 7VA Outputs : 3x 12Vdc

1I2

C cable: 2-wire shielded cable connect SDA and SCL as wires and connect shield to Gnd (0V).

Maximum length I2C cable is 5 meter.

RS485 cable: 2xTwisted-pair with in pair-1 line A and B, in pair-2 2xGnd (or 1 wire with Gnd) and shield only

at one side to earth (PE). Make no side branches. Maximum total length of RS485 cable is 1 KM. Terminate the cable at both ends by connecting a resistor of 250 Ohm between line A and B.

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2. Functional specifications.

The MC785-DF KLIMA has the following control functions:

• cooling

• heating

• dehumidfying

• humidifying Further more the controller has an alarm relay, which is activeted when the alarm levels are exceeded or a sensor is broken.

Four addition temperature sensors can be connected to the Controller thru the LMS 4x Pt100 Module. These sensors can assigned as control-, defrost- or productsensor.

• In case that extra sensors are assigned as control sensor to the controller, it regulates the temperature

with the average temperature of these sensors.

• In case that extra sensor are assigned as defrost sensor to the controller, it uses the lowest

temperature of these defrost sensors to defrost the controller.

• In case that extra sensors are assigned as product sensor to the controller, it uses them only for

readout.

A selection between four different modes of defrosts can be made:

• no defrost,

• natural defrost

• el ectric defrost

• hotgas defrost

The controller has five analog outputs available with a range of 0/+10Vdc (CH-1 to CH-5). Whereby CH-1 is connected direct to the controller and CH-2 untill CH-5 is connected at the LMS analog out module (out-1 untill out-4). From which four outputs (CH-1 to CH-4) are programmable as:

• measuring signal

• setpoint signal

• P(I) control for cooling

• P(I) control for heating

• P(I) control for humifying

• P(I) control for dehumifying And one output CH-5 has the function of the highest output percentage of CH-1 (Out-1 at the MC785-DF KLIMA) and CH-2 (Out-1 at the LMS Anaolg-out module).

The controller has a digital input contact which is used as day/night input.

The selection of the above-mentioned settings is done thru the Internal Parameters.

The controller can also be connected to the ALFANET, thru the RS485-network connection, to view or set the controller.

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3. Control.

During normal operation the upper displays show the (average) control temperature and measured rel. humidity and the lower displays show the temperature setpoint and the RH setpoint.

3.1 Readout (lowest) defrost temperature and seperate sensors.

Press the DEFR.SENS key to readout the lowest defrost temperature sensor on the temperature display. The setpoint display shows now ‘dEfr’ to indicate that the lowest defrost temperature is being shown.

By pressing the DEFR.SENS key repeatedly the separate sensors will be shown in the temperature display according to the sensor configuration. The setpoint display shows which sensor is being shown:

dEfr : lowest defrost sensor temperature rEG0 : control sensor connected to the controller itself dEf0 : defrost sensor connected to the controller itself. LmS1 : LMS sensor-1 connected at the LMS Pt100 module. LmS2 : LMS sensor-2 connected at the LMS Pt100 module. LmS3 : LMS sensor-3 connected at the LMS Pt100 module. LmS4 : LMS sensor-4 connected at the LMS Pt100 module.

If for 10 seconds no key is pressed, than the control will return to it’s normal operation and shows the (average) control temperature and it’s setpoint again.

3.2 Changing the temperature setpoint.

Push the SET key next to the temperature setpoint display. The setpoint starts flashing. The setpoint can be changed with the UP and DOWN key. By pushing the SET key once again, the setpoint shows contineously in the display.

Is the MC 785-DF KLIMA in the day mode (DAY LED on) and should the night setpoint be watched or changed, push the UP or DOWN key and next on the SET key. The LED of the other mode flashes, the setpoint appears flashing in the display. Changing of the setpoint again wuth the UP or DOWN keys and acknoledge with the SET key. In the same way the day setpoint can be watched or changed if the MC 785-DF KLIMA is in the night mode.

3.3 Changing of the RH setpoint.

Push the SET key next to the RH setpoint display. The setpoint starts flashing and can be changed with the UP or DOWN keys. By pressing the SET key again the setpoint appears contineously in the display.

If the instrument is in the day mode (DAG LED on) and the night setpoint needs to watched or changed, push the UP or DOWN key and next push the SET key. The LED of the other mode flashes, the setpoint appears flashing in the display. Changing of this setpoint again with the UP or DOWN keys and acknoledge with the SET key. In the same way the day setpoint can be watched or changed if the MC 785 KLIMA is in the night mode.

3.4 Resetting the alarm.

As soon as an alarm situation occurs and a failre message appears in the temperature display can, by pushing the RESET ALARM key, the alarm be reset. The error meaasage remains in the display, till the cause of the failure is solved.

3.5 Day/night input.

If the day/night input is closed, the MC 785-DF KLIMA switches from day to night mode. The night LED light. If the input is opened, the controller switches back to the day mode.

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3.6 Manual start of defrost.

By pressing the DEFR key, the defrost can be started manually, and therefor independent of the defrost timer. The defrost release temperature is not taken into account. The defrost will always start.

3.7 Operation of fan control.

With the FAN key can be switched between the manual and automatic fan mode. In the manual mode the fan will run contineously, in the auto mode the fan will only run during cooling or heating, including the fan off delay time. During electric defrost the fan will always stop.

3.8 Readout output percentages of the analog outputs CH-1 untill CH-4.

Press the PRG key (and hold it) and than press the DEFR.SENS key to readout the output percentage of analog output CH-1. The output percentage will appear in the temperature display while the setpoint display shows ‘AnA1' to indicate this readout of CH-1.

By pressing the DEFR.SENS key (without the PRG key) the next output percentages will appear in the temperature display while the setpoint display shows which percentage is shown:

Ana1 : Output percentage of analog output CH-1 Ana2 : Output percentage of analog output CH-2 Ana3 : Output percentage of analog output CH-3 Ana4 : Output percentage of analog output CH-4

If for 10 seconds no key is pressed, than the control will return to it’s normal operation and shows the (average) control temperature and it’s setpoint again.

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4. Programming internal settings.

By pressing the PRG and RESET ALARM ket at the same time for more than 5 seconds, the Interne Parameter menu is entered. In the display appears a P with a number behind it. With the UP or DOWN key the required parameter is selected.

If the required parameter is reached, can by pushing the PRG key, the value of the parameter be watched. By simulteaneously pressing the PRG with the UP or DOWN key, the value can be adjusted. After releasingf the keys, the parameter number appears again in the display.

If during 30 seconds no key is touched, the display turn back to the normal operation mode.

4.1 Parameter table.

Nr Description Range Unit Default

P 01 P 02 P 03 P 04

P 05 P 06 P 07 P 08

Differential cooling Offset cooling Differential heating Offset heating

Differential dehumidifying Offset dehumidifying Differential humidifying Offset humidifying

0.1..15

-15..+15

0.1..15

-15..+15

0.1..15

-15..+15

0.1..15

-15..+15

EC EC EC EC

% RH % RH % RH % RH

0.5

0.0

0.5

0.0

1.0

0.0

1.0

0.0

P 10 P 11

P 12 P 15

Offset temperature sensor Offset defrost sensor

Offset RH sensor Defrost sensor present

-10/+10

-15/+15 0 = no, 1 = yes

EC EC

% RH

0.0

0.0 1

P 20

P 21 P 22

Function extra relay (see also P154)

0 = watch alarm 1 = control alarm 2 = cooling 3 = heating 4 = dehumidifying 5 = humidifying 6 = watch alarm not resetable 7 = control alarm not resetable

Differential extra relay Offset extra relay

0..7

0.1..15

-15..+15

0.5

0.0

P 30 P 31

P 32 P 33

P 34 P 35

P 36

Minim um setting temperature setpoint Maximum setting temperature setpoint

Readout above -10EC per 1EC Readout below -10EC per 1EC

Minim um setting RH setpoint Maximum setting RH setpoint

Read out per 1% RH

-40..+50

0 = no, 1 = yes 0 = no, 1 = yes

0..100

0 = no, 1 = yes

EC EC

% RH % RH

-40.0

+50.0

0 1

100

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Nr Description Range Unit Default

P 40

P 41 P 42

P 43 P 44

P 45 P 46

P 47 P 48

Type temperature alarm

0 = No alarm 1 = Absolute alarm 2 = Relative to setpoint

Minim um alarm temperature Maximum alarm temperature

Minim um alarm delay Maximum alarm delay

Temperature control-off at minimum alarm Temperature control-off at maximum alarm

Humidity control-off at m in. temp. alarm Humidity control-off at m ax. temp. alarm

0..2

-40..+50

0..99

0 = no, 1 = yes 0 = no, 1 = yes

EC EC

minutes minutes

-40.0

+50.0

0 0

P 50

P 51 P 52

P 53 P 54

P 55 P 56

Type RH alarm

0 = No alarm 1 = Absolute alarm 2 = Relative to setpoint

Minim um RH alarm Maximum RH alarm

Minim um alarm delay Maximum alarm delay

RH control-off at minimum alarm RH control-off at maximum alarm

0..2

-100..100

0..100

0..99

0 = no, 1 = yes 0 = no, 1 = yes

% RH % RH

minutes minutes

100

0 0

P 60

P 61 P 62

P 63 P 64 P 65

P 66 P 67

Function analog CH-1

0 = Measured temperature 1 = Measured RH 2 = Temperature setpoint 3 = RH setpoint 4 = P(I) cooling 5 = P(I) heating 6 = P(I) dehumidifying 7 = P(I) humidifying

0 V output at 10 V output at

Proportional range Offset proportional range Interval value (999 give only P)

As puls/pauze Puls/pause cycle time

0..7

-100..+100

0.1..15

-15..+15

1..999

0 = no, 1 = yes

5..240

minutes

seconds

-40.0

+50.0

1.0

0.0

999

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Nr Description Range Unit Default

P 70

P 71 P 72

P 73 P 74 P 75

P 76 P 77

Function analog CH-2

0 = Measured temperature 1 = Measured RH 2 = Temperature setpoint 3 = RH setpoint 4 = P(I) cooling 5 = P(I) heating 6 = P(I) dehumidifying 7 = P(I) humidifying

0 V output at 10 V output at

Proportional range Offset proportional range Interval value (999 give only P)

As puls/pauze Pulse/pauze cycle time

0..7

-100..+100

0.1..15

-15..+15

1..999

0 = no, 1 = yes

5..240

minutes

seconds

-40.0

+50.0

1.0

0.0

999

P 80

P 81 P 82

P 83 P 84 P 85

Function analog CH-3

0 = Measured temperature 1 = Measured RH 2 = Temperature setpoint 3 = RH setpoint 4 = P(I) cooling 5 = P(I) heating 6 = P(I) dehumidifying 7 = P(I) humidifying

0 V output at 10 V output at

Proportional range Offset proportional range Interval value (999 give only P)

0..7

-100..+100

0.1..15

-15..+15

1..999

minutes

-40.0

+50.0

1.0

0.0

999

P 90

P 91 P 92

P 93 P 94 P 95

Function analog CH-4

0 = Measured temperature 1 = Measured RH 2 = Temperature setpoint 3 = RH setpoint 4 = P(I) cooling 5 = P(I) heating 6 = P(I) dehumidifying 7 = P(I) humidifying

0 V output at 10 V output at

Proportional range Offset prop. range Interval value (999 give only P)

0..7

-100..+100

0.1..15

-15..+15

1..999

minutes

-40.0

+50.0

1.0

0.0

999

P 100 P 101 P 102

P 103 P 104

Start delay cooling Stop delay cooling Parameter 100/101 in seconds or minutes

Minim um on-tim e cooling Minim um off-time cooling

0..99

0..99 0 = sec, 1 = min

0..99

minutes minutes

0 0 0

0 0

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Nr Description Range Unit Default

P 110 P 111

P 112 P 113

Switch off delay fan Switch on temperature fan after defrost

Switch on delay fan after defrost Drainage time

0..99

-40..+50

0..99

minutes

minutes minutes

2.0

0 0

P 120

P 121 P 122 P 123 P 124

P 125 P 126

P 127 P 128

Defrost mode

0 = no defrost 1 = natural defrost 2 = elektric defrost 3 = hot gas defrost

Defrost interval Maximum defrost time End of defrost temperature Defrost release temperature

If the evaporator temperature is higher than the release temperature the

defrost is not started. Defrost relay during natural defrost active Defrost based on compressor run tim e

Display fixed during defrost Maximum tim e display fixed

0..3

1..99

-10..+30

-40..+50

0 = no, 1 = yes 0 = no, 1 = yes

0 = no, 1 = yes

1..99

hours

minutes

EC EC

minutes

12 30

5.0

2.0

0 0

P 130

P 131

P 132

P 133

P 134

P 135 P 136 P 137

If cooling on then

0 = nothing off

1 = humidify off

2 = dehumidify off

If heating on then

0 = nothing off

1 = humidify off

2 = dehumidify off

If humidify on then

0 = nothing off

1 = cooling off

2 = heating off

If dehumidifying is active then

0 = notthing

1 = cooling off

2 = heating off

Dehumidifying by

0 = nothing

1 = cooling contact

2 = heating contact

During humidifying fan on During dehumidifying fan on During heating fan on

0..2

0 = no, 1 = yes 0 = no, 1 = yes 0 = no, 1 = yes

0 0 1

P 140 Day/night function

0 = day/night function off

1 = day/night function on

2 = day/night function on and

humidity control off

0..2 - 0

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Nr Description Range Unit Default

P 145 P 146 P 147 P 148

Fan switch-on threshold P(I) cooling Fan switch-on threshold P(I) heating Fan switch-on threshold P(I) dehumidifying Fan switch-on threshold P(I) humidifying

*) The fan becomes active as the

output percentage of a analog output with this function is above the treshold.

0..100

% % % %

50 50 50 50

P 150

P 151 P 152 P 153 P 154 P 155 P 156

Relay cooling

0 = no

1 = RY1 (MC 785-DF KLIMA)

2 = RY2 (MC 785-DF KLIMA)

3 = RY3 (MC 785-DF KLIMA)

4 = RY4 (MC 785-DF KLIMA)

5 = RY5 (MC 785-DF KLIMA)

6 = RY1 (LMS relay module)

7 = RY2 (LMS relay module)

8 = RY3 (LMS relay module)

9 = RY4 (LMS relay module) Relay heating Relay humidify Relay dehumidify Relay extra function (see also P20) Relay defrost Relay fan

0..9

4 3 2 1 6 7

P 160 P 161

Network number Log interval

1..250

0..120

minutes

1 5

P 170

P 171 P 172 P 173

Function LMS Pt100-1

0 = none

1 = extra control sensor

2 = extra defrost sensor

3 = product sensor Function LMS Pt100-2 Function LMS Pt100-3 Function LMS Pt100-4

0..3

0 0 0

P180 P181 P182 P183

Offset LMS Pt100-1 Offset LMS Pt100-2 Offset LMS Pt100-3 Offset LMS Pt100-4

-15..+15

EC EC EC EC

0.0

P 190 P 191 P 192

Software version (read only) Serial number (read only) Production date (read only)

year/wk

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5. Operation of the relay outputs.

5.1 Operation of the cooling and heating. The cooling (default RY5) switches if the temperature is higher than setpoint + offset cooling + differential cooling and switches off if the temperature is lower than setpoint + offset cooling.

The heating (default RY4) switches if the temperature is lower than setpoint + offset heating - differential heating and switches off id the temperature is higher than setpoint + offset heating.

5.2 Operation of the humidification and dehumidification The dehumidification (default RY2) switches on if the RH is higher than setpoint + offset

dehumidification + differential dehumidification and switches off if the RH is lower than setpoint + offset dehumidification.

The humidification (default RY3) switches on if the RH is lower than the setpoint + offset humidification - differential humidification and switches off if the RH is lower than setpoint + offset humidification.

5.3 Operation of defrost. There are four different methods for the defrost.

1. No defrost.

2. Natural defrost.

Before the defrost is started, a check is done to see if the temperature of the defrost sensor is lower than the defrost release temperature (P 94). If this is not the case, the defrosted is skipped. If the defrost starts, the cooling is switched off and the defrost relay is on. The fan will run continuously during the defrost. The defrost is stopped if the end-of-defrost temperature is reached (P 93), with a limit on the maximum defrost time (P 92).

3/4. Electric/hot-gas defrost.

Before the defrost is started, a check is done to see if the temperature of the defrost sensor is lower than the defrost release temperature (P 94). If this is not the case, the defrosted is skipped. If the defrost starts, the cooling is switched off, the fan stops and the defrost relay is switched on. The defrost is stopped if the end-of-defrost temperature is reached (P 93), with a limit on the maximum defrost time (P 92). After defrost the fan will start when the defrost-sensor reaches a temperature lower than the fan release temperature (P 81).

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6. Sensor calibration.

With parameters P10, P11, P12, P180, P181, P182 and P183 the temperature sensors and RH sensor can be calibrated.

Indicates the temperature sensor e.g. 0,2°C too much, the according temperature offset should be set 0,2°C lower.

7. Alarms.

If the extra relay is set as watch alarm (parameter P20=0), in normal mode the relay is on and drops during alarm. In this mode also an alarm is given if the power supply is lost. If the extra relay is programmed as control alarm (P20=1), in normal mode the relay is off and switches on during alarm.

During alarm the alarm LED on the front flashes. Depending on the setting of the Internal Parameters the control will stop or continue. An alarm can be caused by:

Sensor failure : E1 = Temperature sensor broken

E2 = RH sensor broken E7 = Defrost sensor broken

Temperature alarm : E3 = Minimum temperature alarm

E4 = Maximum temperature alarm

RH alarm : E5 = Minimum RH alarm

E6 = Maximum RH alarm

The temperature alarms are shown in the temperature display (left top). The RH alarms are shown in the RH display (right top).

By pressing the RESET ALARM key the extra relay will, if configured as alarm relay, be reset. The error message remains during the failure in the display. Also, the alarm LED will continue to flash.