Danfoss EKC 531D1 Instructions page 4

Condenser couplings
When the compressor relays have been established the turn comes to the
fan relays.
The first vacant relay (DO1-DO8) will become the first fan relay. It will be
followed by the subsequent relays. If more relays are required than the
vacant DO relays, a relay module can be connected to the analog output.
The function is, as follows:
If there are up to four external fans on an EKC 331:
Output signal from EKC 531D1
In EKC 331 the voltage range must be set to 0-5 V ("o10" = 6).
In EKC 331 the number of steps must be set to 4 ("o19" = 4) (also when
fewer fans are connected).
Connection
Alternating start-up of fans (only if c29 is 11 to 18)
The fans can be defined to start alternately when they have all been
stopped.
The first time regulation is started, fan 1 will be started first – the regulation
determines whether additional fans will be started.
After the next time all fans are stopped, fan 2 will be the first to be started,
and so on.
Fan 1 will again be the first fan to be started when the rotation has been
through the total number of fans.
If there is more than one fan on an EKC 331, it will not be possible to start
the other fans first. Here, the fan with the lowest voltage step will always be
the one which is started first.
If the entire condenser capacity is to be controlled by a
frequency converter, EKC 531D1 must send an analog signal
about the required capacity ("c29" = 9).
The signal varies from 0 to 10 V. Signal and capacity have the
following context.
4 Instructions RI8HU452 © Danfoss 10/2006
If there are more than four external fans on two EKC 331 units:
2.
1.
Output signal from EKC 531D1
In the first EKC 331, set 0-5 V ("o10" = 6).
In the second EKC 331, set 5-10 V ("o10" = 7).
In both EKC's the number of steps must be set to 4 ("o19" = 4) (also when
fewer fans are connected to the second EKC).
Connection
EKC 531D1