Eliwell Televis EWCM 809/NH3/S User Manual

AVAILABLE VERSIONS
(from the 21/05/96, software n. 23)

EWCM 809/NH3/S (ammonia) with pres­sure (4…20 mA programmable) or with
NTC temperature input probe and with se­rial connection for connection to the TELE­VIS system.

GENERAL FEATURES

The new EWCM 809/NH3/S is a controller
designed specifically for the control of a
machine room in a refrigeration system.
The main input comes from a 4…20 mA
pressure transducer for ammonia or from a
NTC temperature probe, while up to 9 re­lay outputs with their digital alarm inputs
are provided for the management of the
single units, multistep compressors and
compressors having different power.
The EWCM 809/NH3/S is provided with
the management of the high and low pres­sure alarms and the management of the
high and low pressurestat alarms.
The two programmable setpoints “normal”
and “economy”, can be displayed in three
programmable units of measurement: Bar,
°C or °F. This feature which is available at
any time, and not only during the configu­ration, makes the controller easy to use
and adaptable to the preference of the
User, the Installer or the Maintenance per­sonnel.
A protection system executes a continu­ous diagnosis of the controller; in the event
of a malfunction, a dedicated output is
used to transfer the control of the main re­frigeration plant to an emergency system
which will take over until service personnel
corrects the situation.

FRONT KEYPAD

“PRG” button: to have access the pro­gramming.
“HRS” button: to display/reset the run­ning hours of each compressor.
“MAINT” button: to display/modify the
“available” or “in service” status of each
compressor.
“SET” button: to display/modify the “nor­mal” or the”economy” Setpoints.

“UP” button: to increase the figures.
“DOWN” button: to decrease the figures.
“MUTE” button: to silence/reset an

alarm.
“LOCK led”: to dispaly the keyboard lock
function.
“ALARM” led: to display an alarm condi­tion.
“COMPRESSOR & STAGES” leds: red
and green leds to display the output com­pressor status.
4 DIGIT DISPLAY: it shows the input
probe value, the default unit of measure­ment can be programmed with “dEU” pa­rameter. As soon as an alarm occurs the
display will switch back and forth between
the probe read-out and the alarm code la­bel.

INPUT AND OUTPUT

Alarm relay output: remote alarm, the
terminals 1 and 2 are closed when there is
an active alarm.
Safety relay output: the terminals 3 and
4 are open when an EWCM failure ap­pears.
Pressurestat alarm input: high and low
pressurestat input alarms (terminals 5 and
6, “SEP” parameter).

Power supply: input terminals 9 and 10.
Economy set switch: to activate the

HOW IT IS MADE

• Housing: black ABS plastic,
72x144 mm, depth 120 mm

• Connections: quick-disconnect
screw terminal block

• Type of refrigerant: ammonia

• Suction sensor input: NTC or
4…20 mA pressure transducer
(scaleable)

• One pressurestat alarm input

• Global alarm output: relay 6(3)A
250V AC

• Controller breakdown output: re­lay 6(3)A 250V AC

• Configurable outputs: 9 relays
outputs 6(3)A 250V AC

• Alarm inputs: 9 optoisolated in­puts (the same voltage of the sup­ply)

• Serial connection: RS-485 port for
connection to the Televis system

• Consumption: 6 VA

• Power supply: 12, 24, 110, 220 Vac
±10%, 50/60 Hz

WHAT IT IS

The EWCM 809/NH3/S is a con­troller designed specifically for the
control of a machine room in a re­frigeration system.
EWCM 809/NH3/S provides control
management of the compressors
(single units, multistage systems or
compressors having different pow­er).

EWCM 809/NH3/S

rel. 5/98 ing

compressors manager, model for ammonia

PLUS PRODUCT

• Alarm circuit combined with each
compressor

• Clock to set the various operation
setpoints in various time periods

• UL approval pending

2EWCM 809/NH3/S 5/98 ing

economy setpoint (terminals 13 and 14
have free voltage contacts, “rSIP” parame­ter).

Suction probe: input terminals 15 and 16.
Televis System: RS 485, input terminals

19, 20 and 21.
Compressor alarms inputs: when ac­tive, the compressor output is swiched off
(terminals from 22 to 39, “ALIP” parame­ter).
Compressor relay outputs: to supply
the contactors of the compressors (termi­nals from 44 to 61).

PARAMETER PROGRAMMING
ENTERING THE PROGRAMMING
MODE

The EWCM is provided with two levels of
parameters programming: operating “oPr”
and Configuration “CnF”.
To have access the “oPr” menu, push and
release the “prg” button and then the “UP”
arrow.
To have access the “CnF” menu, push the
“prg” button twice and then the “UP” ar­row.
If a password has been activated, the
“PAS” label will be showed before entering
the programming.
To exit the programming mode, push the
“prg” button another time, all the changes
will be automatically memorized.

HOW TO DISPLAY AND MODIFY
THE PARAMETERS

After entering programming, to display a
parameter label push the “UP” or “DOWN”
arrows:

- to show a parameter value push the “set”
button;

- to modify the parameter value push the
“UP” or “DOWN” arrows;

- to exit the parameter value push the ”set”
button.

PASSWORDS

The passwords “Psc” and “Pso” are pro­vided to enter the Configuration and
Operating parameters programming.
To activate the password enter the pro­gramming mode, select the password la­bel and set the password number.

CONFIGURATION PARAMETERS

System capacity

CPnU: ComPressor nUmber.
Number of compressors installed.
CtyP: Compressor tyPe.
0 = compressors having different power
(Neutral Zone Control);
1 = compressors having the same power
(Proportional Control).
Note: compressors having the same pow­er, but without partial reduction valves.

- Neutral Zone (dead band) is used with
compressors having a big power.

- Proportional control is used with small
power compressors.

CPSt: ComPressor Step.
Number of steps of each compressor (only

Parameter Description Range Default Unit

CONFIGURATION PARAMETERS

CPnU ComPressor nUmber 1…11 7 number

Ctyp Compressor tyPe 0 / 1 1 number

CPSt ComPressor Step 1…6 1 number

PC1…PC11 Power Compressor 1…11 1…255 1 number

FtyP Freon tyPe / / /

PA04* Pressure At 0…4 mA 0…8 0,5 Bar

PA20* Pressure At 0…20 mA 0…31 8 Bar

CAL** CALibration –0.5…0.5 0 Bar

CAL*** CALibration –5…5 0 °C

SEP SEt (alarm) Polarity 0 / 1 1 number

rSIP reduced Set Input Polarity 0 / 1 1 number

ALIP ALarm Input Polarity 0 / 1 1 number

StPP Step outPuts Polarity 0 / 1 1 number

Psc Password configuration 0…255 0 number

tAb tAble of parameters / / /

OPERATING PARAMETERS

Pri Primes 0…59 0 minutes

HoUr HoUrs 0…23 0 hours

daY dAY 1…7 0 number

dEU dEfault Unit 0 / 1 / 2 0 number

Pbd Proportional band 0.1…5 0,4 Bar / °C / °F

onon on/on (compressor) 0…255 5 minutes

oFon oFF/on (compressor) 0…255 5 minutes

don delay on 0…5000 15 seconds

doF delay oFF 0…255 5 seconds

donF delay on/oFF 0…255 15 seconds

FdLy First deLay on 0 / 1 1 number

FdLF First deLay oFF 0 / 1 1 number

odo output delay at on 0…255 0 seconds

LSE Lower SEt 0.1 / HSE 0.2 Bar / °C / °F

HSE Higher SEt LSE / 25 5 Bar / °C / °F

StrS Start time reduced Set 0…24 0 hours

SPrS Stop (time) reduced Set 0…24 0 hours

rSd1…rSd7 reduced Set day 1…7 0 / 1 0 number

UAro Unit Alarm override 0 / 1 1 number

Aro Alarm override 0…255 15 minutes

PAO Power Alarm Override 0…255 30 minutes

LAL Lower ALarm 0.01…25 5 Bar

HAL Higher ALarm 0.01…25 5 Bar

tAo time Alarm override 0 255 minutes

SEr SErvice 1…9999 3000 hours

PEn Pressurestat Errors number 0…15 5 number

PEI Pressurestat Errors Interval (time) 0…15 15 minutes

CPP Compressor Probe Protection 0 / 1 0 number

SPr Step Probe protection 0 / CPnU 1 number

PoPr Power (with faulty) probe 0 / n 0 number

rELP rELative Pressure 0 / 1 1 number

Loc keyboard Lock function 0 / 1 1 number

Pso Password operating 0…255 0 number

FAA FAmily Address 13…14 13 number

dEA dEvice Address 0…14 0 number

DEFAULT SETTINGS - STANDARD MODELS