1592023130 XM670K_XM679K GB r4.2 26.06.2017.docx
XM670K - XM679K
2/10
5.7
SENSORS FOR SUPERHEAT CONTROL
–
ONLY FOR XM679K
Temperature probe:
Pb6
terminals [
19
] - [
20
] without any polarity.
Select the kind of sensor with
P6C
parameter.
Pressure transducer: Pb5
terminals:
[
21
] = input of the signal; [
22
] = Power Supply for 4to20mA transducer;
[
20
] = GND; [
23
] = +5Vdc power supply for ratiometric pressure
transducer.
Select the configuration of the transducer with parameter
P5C
.
5.8
HOW TO USE ONLY ONE PRESSURE TRANSDUCER ON MULTIPLEXED APPLICATIONS
A working LAN connection is required (green LED lit on all XM670-XM679K boards of the same LAN). Connect
and configure a pressure transducer only on
one
XM670-XM679K of the network. Afterwards, the value of
pressure read by the unique transducer connected will be available to each device connected to the same LAN.
By pressing
UP ARROW
button, the user will be able to enter a fast selection menu and to read the value of the
following parameters:
dPP
= measured pressure (only on master device);
dP5
= value of temperature obtained from pressure
temperature conversion;
rPP
= pressure value read from remote location (only for slave devices).
Examples of error messages:
dPP = Err
the local transducer read a wrong value, the pressure is out of the bounds of the pressure
transducer or the
P5C
parameter is wrong. Check all these options and eventually change the transducer;
rPF
the remote pressure transducer is on error situation. Check the status of the onboard GREEN LED: if
this LED is OFF the LAN is not working, otherwise check the remote transducer.
LAST CHECKS ABOUT SUPERHEAT
On the fast access menu:
dPP
is the value read by the pressure gauge;
dP6
is the value read by the temperature probe, temperature of the gas on the outlet section of the evaporator;
SH
is the value of the superheat. The
nA
or
Err
messages mean that the superheat has no sense in that
moment and its value is not available.
5.9
HOW TO CONNECT MONITORING SYSTEM
1)
Terminals [
36
] [-] and [
37
] [+].
2)
Use shielded twisted cable. For example Belden®
8762 o 8772 or cat 5 cables.
3)
Maximum distance 1Km.
4)
Don’t connect the shield to the earth or to GND
terminals of the device, avoid accidental contacts by
using insulating tape.
Only one device for each LAN has to be connected to the RS485 connection.
The
Adr
parameter is the number to identify each electronic board.
Address duplication is not permitted
, in
this case the synchronized defrost and the communication with monitoring system is not guaranteed (the
Adr
is
also the ModBUS address).
5.10
DIGITAL INPUTS
1)
The terminals from [
30
] to [
33
] are all free of voltage;
2)
Use shielded cable for distance higher than one
meter;
For each input, has to be configured: the polarity of
activation, the function of the input and the delay of
signaling.
The parameters to perform this configuration are
i1P
,
i1F
,
i1d
respectively for polarity, functioning and delay. The
i1P
can be:
cL
= active when closed;
oP
= active when opened. The
i1F
parameter can be:
EAL
= external alarm,
bAL
= serious lock alarm,
PAL
= pressure switch alarm,
dor
= door switch,
dEF
= external defrost,
AUS
= auxiliary
activation command,
LiG
= light activation,
OnF
= board On/OFF,
FHU
= don’t use this configuration,
ES
=
day/night,
HdY
= don’t use this configuration. Then there is
i1d
parameter for delay of activation. For the others
digital inputs there are a set of the same parameters:
i2P
,
i2F
,
i2d
,
i3P
,
i3F
,
i3d
.
5.11
ANALOG OUTPUT
Selectable between 4 to 20mA and
0 to 10Vdc.
Use CABCJ15 to perform the connections
It’s located near the terminal [
39
] on a 2-
pin connector. It’s possible to
use the output to control anti-sweat heaters
through a chopped phase controller XRPW500 (500watt) or family XV...D or XV...K.
6.
QUICK REFERENCE GUIDE: HOW TO RUN THE SELF ADAPTIVE
REGULATION IN 4 STEPS.
1.
After wiring the XM679K,
set the proper gas
via
Fty
parameter. Pre-set gas is R404A.
2.
Configure the probes
:
-
Regulation and evaporator
probe are preset as NTC. If another kind of sensors is used, set it via
P1c and P2c parameters.
-
Superheat evaporator outlet probe
is pre-set as Pt1000, if another kind of sensor is used, set it
via P6c parameter.
-
The
PP11
(-0.5÷11bar) is pre-set as
pressure probe.
It operates at relative pressure (
Pru
= rE).
If you’re using a ratiometric transducer, set
P5c = 0-5
, then use parameters
PA4
and
P20
to set
the range
NOTE:
check the pressure gauge reading with the value of dPP, press the
UP
arrow once to enter
the
Fast Access Menu
. If ok, proceed; otherwise solve the situation before proceeding acting on
par. Pru, PA4 and P20.
3.
Set the parameters for self adaptive regulation of superheat
NOTE:
the parameters
Pb
(regulation band) and
Int
(integral time) are automatically calculated by the
controller
-
Set
CrE = no,
this disable the continuos regulation of the temperature. Default is CrE = no.
-
Set
SSH
,
superheating setpoint
: a value between 4 and 8 is acceptable. Default is SSH=8
-
Set
AMS = y
to start the
self adaptive regulation
. Default is AMS = y
-
Set
ATU = y
to start the search of the
lowest stable superheat
. Default is ATU = y. This function
reduces automatically the setpoint in order to optimize the use of the evaporator, keeping, at the
same time, the superheating regulation stable. The minimum allowed SH set point is LSH+2°C.
-
Set
LSH
,
low superheating limit
: a value between 2-4 is acceptable. Default is LSH = 3
-
Set
SUb, pressure filter
: Default is SUb = 10. The value can be increased up to 20 in case of too
fast response of the pressure variations.
4.
Set the parameters for the temperature regulation
-
Set the temperature
setpoint
. Default is -5°C
-
Set
the differential HY
: Default is 2°C.
-
If the
capacity of the valve
is higher than requested, it can be reduced by the par.
MNF
(Default
is 100). A proper setting of MnF will reduce the time that the algorithm takes to reach the stability.
MNF
value doesn’t affect the band witdh
7.
USER INTERFACE
7.1
ICONS
Cooling output
↓
With icon ON the output is
active, while with blinking icon
there is a delay.
MEASUREMENT UNIT
°C, Bar
and
(time)
are
ON depending on the
selection.
Light
→
←
Fan
Defrost
→
AUX
←
Auxiliary relay
Energy saving
→
←
Multimaster Enabled
Generic alarm
→
←
Clock / time
DURING PROGRAMMING
: blink the measurement units of temperature and pressure
7.2
KEYBOARD COMMANDS
Single commands:
LIGHT relay
Press light button.
AUX relay
Press down arrow.
Manual defrost
Press and hold for 3 sec the defrost button
ON/OFF
Press for 3 sec the
ON/OFF
button (if the function is enabled).
Energy Saving
Press for 3 sec the
ON/OFF
button (if the function is enabled).
Double commands:
Press and hold for about 3 sec to lock (
Pon
) or unlock (
PoF
) the keyboard.
Pressed together to exit from programming mode or from menu; on submenus
rtC
and
EEV
this combination allow to come back to previous level.
Pressed together for 3 sec allow to access to first level of programming mode.
7.3
HOW TO MODIFY THE SET POINT FOR AIR TEMPERATURE REGULATION
The thermostat set point is the value that will be used to regulate the air temperature. The regulation output is
controlled by the electronic valve or by the relay.
BEGIN
Press SET button for 3 sec, the measurement units will blink together.
