Technical Manual Cold Storage Controller EVP 3150-1 and EVP 3150-2
Page 15
Networking of controllers via
E-LINK
The EVP-controller can be used as intelligent
cold storage controller in co-operation with the
compound control system VPR.
In this case, the VPR central processing unit
monitors the EVP.
When the EVP's are connected to the compound
controller, each one needs an individual address
("
P90
", Mode Page)
For the EVP's there is a possibility of assigning
each controller to a certain compound ("
P01
",
Mode Page). This enables the VPR to transmit
specific information to the cold storage control-
lers assigned to the compound where a failure
occurs. Additionally, the information exchange
allows different optmizing methods for suction and
condensing control.
More detailed information you will find in the techni-
cal manuals of the VPR compound systems.
Behavior in case of a compound failure
If an EVP is assigned to a certain compound and a
disturbance occurs, the unit responds as follows:
● The solenoid valves close
● The fan switches off
● A defrost will be terminated. A new defrost
period is only possible after the compound
problem is solved.
To see if this function is released, look at
"
L41
" (Actual Values Page).
"
0
" = solenoid valve closed
"
1
" = solenoid valve open
"
oFF
" = solenoid valve closed via interface
The EVP can be networked together with other
ELREHA control devices via an RS-485-2-wire
databus, which enables up to 78 controllers to
communicate. For communication, the
E-LINK
transmission protocol is used.
Each controller in a network has its individual
address ("
P90
", Mode Page). The data transmission
rate is factory set to "Aut(o)", this means that it will
be identified automatically. If necessary, the rate can
also be set manually ("
P91
", Mode Page).
This address is necessary for selecting the right
controller when a data package is transmitted on
the network bus. If the controller is used outside a
network, these parameters are of no importance.
Remote control at Frontend Systems
EVP controllers can be operated remotely via
interface when they are connected to Frontend
Systems such as SMZ or VPR.
In this case, the Frontend System shows the EVP's
display contents and the keys of the frontend work
as if they where the keys of the EVP.
Wiring of data lines
The scheme beside shows briefly, how dataline
wiring of several controllers is made. At each con-
troller, the shield has to be connected to the nearest
ground terminal. Also the ground connector of the
controller and terminal #28 must be connected to
the nearest ground terminal.
This will assure good interference suppression,
even for long datalines between the controllers.
Communication with the VPR Compound Controller System
Configuration / Service via PC
The controller can be linked to a PC via its RS-485
interface. By using the PC-software „Coolvision-
MES“, parameters can be changed, they can be
saved to the hard disk (download) and can be send
to other controllers (upload).
To do this, the PC must be equipped with an RS-
485 interface (internal card or an converter of the
SSC-series).
Data transmission disturbances
If the controller gets no new information from
the VPR, it continues working with the current
settings.
If there was an order from the VPR to close the
solenoid valves and a technical defect interupts
the data transmission for more than 30 minutes,
the EVP ignores this order and starts working
normally.
When data transmission is restored, the EVP will
work again immediately according to the commands
of the VPR.
Note
Protective Earth
Earth
analog out
N
L
N
L
1
2
3
4
5
OK/DI 2
Netz
Mains
9
7
6
8
Relais K1
20
24
21 22 23
28
NDO
DO
RS
485
26
25
27
analog out
Relais K1
6
N
L
N
L
2
1
3
4
5
Netz
Mains
OK/DI 2
9
7
8
25
21
20
NDO
24
22 23
DO
RS
485
28
26 27
relay k1
relay k1
