Emerson EC2-552 Mode D'emploi

G e n e r a l i n f o r m a t i o n :
The EC2-552 has been designed to control single compressor or tandem compressor
condensing units with a Copeland Scroll Digital
control. The purpose of the controller is to maintain suction pressure at a pre-defined
level by modulating compressors and to keep condensing pressure to a minimum by
varying fan motor speed.
The PT5 pressure transmitter (1) senses suction pressure. The Digital Scroll
Compressor (6) operates as the base load compressor. Capacity modulation is
achieved by temporarily unloading the compressors scroll sets with the Pulse Width
Modulated (PWM) signal (11) which controls the compressor unloading valve (12).
In tandem compressor condensing units, the single stage compressor (7) will only be
turned on when demand exceeds the refrigeration capacity of the Digital Scroll
Compressor. The discharge temperature thermistor of the Digital Scroll Compressor
should be connected to the Disch. Temp. input (5) of the controller and the volt-free
digital inputs (3) and (4) should be connected to the serial alarm loops of both
compressors for feedback of compressor tripping.
1
Scroll compressor
0
100%
Digital scroll
compressor
10%
0%
Two control loops with the same suction pressure setpoint P0 modulate the
compressors. The dead band control loop with dead band P1 switches the single stage
compressor on or off, whereas a PI control loop modulates the Digital Scroll base
load compressor between approximately 10% and 100% capacity. Being the base
load compressor, the Digital Scroll Compressor will never be switched off while the
single stage compressor remains on.
The PT5 pressure transmitter (2) senses condensing pressure and feeds the signal
into a control loop which generates a 0...10V output signal (10) to modulate
condenser fan motor speed by using the EMERSON FSP Fan Speed Power Module.
The control algorithm for condensing pressure is generating a proportional transfer
characteristic:
100%
0%
P0 = condensing pressure setpoint for the fan.
P1 = proportional pressure band within the fan speed is controlled proportional
S a f e t y i n s t r u c t i o n s :
• Read operating instructions thoroughly. Failure to comply can result in device
failure, system damage or personal injury.
• According to EN 13313 it is intended for use by persons having the
appropriate knowledge and skill.
• Do not exceed the specified maximum ratings for pressure, temperature,
voltage and current.
• Before installation or service disconnect all voltages from system and device.
• Do not operate system before all cable connections are completed.
• Entire electrical connections have to comply with local regulations.
• Disposal: Electrical and electronic waste must NOT be disposed of with other
commercial waste. Instead, it is the user responsibility to pass it to a
designated collection point for the safe recycling of Waste Electrical and
Electronic Equipment (WEEE
information, contact your local environmental recycling center.
Emerson Climate Technologies GmbH
Am Borsigturm 31 I 13507 Berlin I Germany
Operating instruction
EC2-552 Condensing Unit Controller
TM
compressor and variable fan speed
P1
P0
P0
setpoint
P1
P0
pressure
directive 2012/19/EU). For further
www.emersonclimate.eu
I n s t a l l a t i o n :
• The EC2-552 can be mounted in panels with a
71 x 29 mm cutout. See dimensional drawing below
for space requirements including rear connectors.
• Push controller into panel cutout. (1)
• Make sure that mounting clamps are flush with
outside of controller housing
• Insert allen key into front panel holes and turn
clockwise. Mounting clamp will turn and gradually
move towards panel (2)
• Turn allen key until mounting clamp barely touches
panel. Then move other mounting clamp to the same
position (3)
• Tighten both sides very carefully until controller is
secured. Do not over tighten as mounting clamps
will break easily.
E l e c t r i c a l i n s t a l l a t i o n :
• Refer to the electrical wiring diagram (right) for electrical connections. A copy of
this diagram is labelled on the controller.
• Use connection wires/cables suitable for 90°C operation (EN 60730-1)
• EC2 analog inputs are for dedicated sensors only and should not be connected to
any other devices. Volt free digital inputs should only be connected to serial control
loops or relays with gold contacts. They should not be connected to any other
devices
pressure
• Use a class II category transformer for 24 VAC power supply (EN 60742). Do not
ground the 24 VAC lines. We recommend to use one transformer per EC2
controller and to use separate transformers for 3rd party controllers, to avoid
possible interference or grounding problems in the power supply. Connecting any
EC2 inputs to mains voltage will permanently damage the EC2.
E C 2 - 5 5 2 d i s p l a y / I R r e m o t e c o n t r o l u n i t : ( L E D s )
The data to be shown on the display can be selected by the user. In case of an alarm,
the alarm code is displayed alternately with the selected data. The user can inhibit
the alarm code.
• Press the SEL button to scroll through all possible displayable data. The display
will show for one second the numerical identifier of the data and then the selected
data. After two minutes the display will return to the by parameter /1 selected data.
Display indicates suction side - C1
Ethernet activity LED
(only active when service pin is pressed)
Display indicates condenser side - C2
Display indicates pressure in bar
Date: 02.05.2017
Alarm condition
Compressor 2 on
Compressor 1 on
EC2-552_OI_ML_R08_864923.docx
Note:
Keep controller and sensor
wiring well separated from
mains wiring. Minimum
recommended distance
30 mm.
IR LED
Fan on