Danfoss AK-PC 551 User Manual

AK-PC 551 User Guide RS8GY302 © Danfoss 2015-06 13
Sc3 oset Temperature oset for regulation with uid reference.
Regulation reference = Sc3 measurement + Sc3 oset
Min: 0 K
Max: 20 K
Fac: 6 K
Min. reference Set the lowest permissible regulation reference here
Min: -25°C (-1.0 bar)
Max: 100°C (159 bar)
Fac: 10°C (5.0 bar)
Max. reference Set the highest permissible regulation reference here
Min: -25°C (-1.0 bar)
Max: 100°C (159 bar)
Fac: 50°C (35.0 bar)
Heat recocery SP Temperature set point for heat recovery function (only when the function is selected during
conguration)
Min: 20°C (-1.0 bar)
Max: 90°C (159 bar)
Fac: 50°C (30.0 bar)
Heat rec. ramp down Ramp-down of regulation reference after heat recovery
Set how quickly the reference for condenser pressure should be made after heat recovery
ends. Enter the change in degrees Kelvin per minute.
Min: 0,1 K
Max: 100 K
Fac: 1 K
Capacity limit night Capacity limitation at night
The speed of the fans can be limited here when regulating using speed control.
During step-by-step activation, the start of the step-by-step process is limited.
Min: 0 %
Max: 100%
Fac: 100%
Gain factor Kp Amplication factor for PI regulation
If the Kp value is lowered, regulation runs more smoothly
Min: 1
Max: 30
Fac: 10
Integration time Tn Integration time for PI regulation
If the Tn value is increased, regulation will run more smoothly
Min: 30 s
Max: 240 s
Fac: 180 s
Fan conguration Conguration of fans
Control sensor Selection of regulation sensor:
• Pc pressure transmitter
• S7 media temperature sensor (Pc must be installed for safety monitoring)
AI-demand
Pc / S7
Fac: Pc
Reference mode Set the reference for regulation here
• Fixed reference; the reference here will be the dened set point
• Variable reference; the reference here will follow the outside temperature, which is meas-
ured with Sc3.
AI-demand
Setpoint / Floating
Fac: Setpoint
Capacity ctrl. mode Set the way in which the fans should be controlled here
• Variable; the fans are controlled by a 0-10 V signal from an analogue output. If it is dened in
“VSD Start via DO”, a relay will be able to start and stop the frequency converter.
• Step; on/o control of fans will be via relays
• Variable + step. The signals are parallel, so external wiring can switch over to step, e.g. if the
frequency converter fails.
AO-demand
Step / Speed
Fac: Step
No. of fans Enter the number of fans here.
For step-by-step activation, select the number of relays. The relays will cut in/out sequentially,
e.g. 123-321.
For speed control, select 1 or higher. No relay is reserved, but the setting makes it possible to
dene the monitoring of fans.
DO-demand
Min: 0
Max: 8
Fac: 0
Control type Normally, PI-regulation is used, but this can be changed to a P-regulation if the design of the
system necessitates this.
• PI Ctrl: Regulation is carried out here with as little deviation between the reference and
measurement as possible.
• P-band ctrl: Capacity is cut in here after proportional regulation.
P / PI
Fac: PI
VSD Start speed Set the start value of the frequency converter here.
The value must be higher than the VSD min. speed value.
Min: 0%
Max: 40%
Fac: 20%
VSD Min speed Set the minimum speed of the frequency converter here.
If lower capacity is required, this minimum speed should be maintained all the way down to
0% capacity. At 0% capacity, the system stops completely.
Min: 0%
Max: 40%
Fac: 10%
VSD Start via DO Dene whether a relay should be connected to the frequency converter start/stop function
here:
• No: no relay
• Yes: the relay pulls in when the frequency converter needs to be in operation.
DO-demand
Yes / No
Fac: No
Monitor fan safety Dene whether safety monitoring of the condenser fans should be performed.
• None: no monitoring
• Individual: a DI input is reserved for each fan
• Common: a DI input that is common for all condenser fans is reserved .
DI-demand
Common /Indi-
vidual
Fac: None
Fan at comp. OFF Select the way in which the fans should be controlled when all the compressors have
stopped.
• Normal regulation: Fans to be controlled in compliance with normal regulation.
• Energy-optimised: Fan capacity will be maintained at between 0 and 49% in a p-band of
5-15 K above reference.
Normal/Optimized
Fac.: Normal
Heat recovery via DI Dene whether a heat recovery cycle should be started with a signal on a DI input here.
• No: No function
• Yes: A DI input is reserved. When a signal is registered, the heat recovery function reference
will become active.
DI-demand
Yes / No
Fac: No

Danfoss AK-PC 551 Specifications

General

Brand	Danfoss
Model	AK-PC 551
Category	Controller
Language	English