OJ Electronics Air2 Fan IO21 Bedienungsanleitung

I N S T R U C T I O N S
OJ Air2 Fan IO21
67168A 10/15 - (OSH)
English
LIST OF FIGURES
The following figures are located at the back of
the instructions:
Fig. 1: OJ Air2 Fan IO21 outline showing elec-
trical connections and pressure tubes
Fig. 2: Configuration example
Fig. 3: Dimensioned drawing
Fig. 4: Connection of pressure tubes
Fig. 5: Connection of Modbus and EC/FC
Fig. 6: Electrical connection of actuators
Fig. 7: External supplementary power supply
Fig. 8: Electrical connection of EC/FC
Fig. 9: Wire layout in connectors "C", "D", "E"
& "F"
Fig. 10: Complete configuration (example)
Fig. 11: Modbus addressing overview
Fig. 12: Supported Modbus commands (hold-
ing registers)
Fig. 13: Supported Modbus commands (input
registers)
INTRODUCTION
OJ Air2 Fan IO21 is an input/output module with
RS-485 RTU Modbus communication specially
designed for installation inside an air handling
unit. OJ Air2 Fan IO21 has been specially
developed for connection and control of Direct
Modbus controlled actuators, damper motors
and valve motors. OJ Air2 Fan IO21 is equipped
with four RJ12 Modbus connectors for Direct
Modbus controlled damper and valve motors
(see fig. 6).
The benefit of Direct Modbus controlled actua-
tors, damper motors and valve motors is that
they can be fully integrated with the ventilation
system. Furthermore, alarms and messages
are always provided via feedback from the
actuators, damper motors and valve motors
whenever situations arise in which they do not
react as expected.
OJ Air2 Fan IO21 is equipped with two pressure
transmitters (see fig. 4) for monitoring purpose,
for example fan operation and filter, air volume
control and collection and distribution of alarm
and control signals. OJ Air2 Fan IO21 uses
standard signals, e.g. 0-10 V DC modulating
control signals, and is connected to standard
components, e.g. standard PT1000 sensors.
PRODUCT PROGRAMME
TYPE PRODUCT
OJ Air2 Fan IO21 Fan input/output module, Direct
Modbus, IP54, 2500 Pa
FUNCTION
• English
OJ Air2 Fan IO21 can with advantage be used
to replace long conventional electric cable con-
• Deutsch
nections, saving both material and installation
time. OJ Air2 Fan IO21 is special in that the
• Français
Direct Modbus controlled damper and valve
motors can be connected direct to OJ Air2 Fan
• Svenska
IO21 using the four built-in RJ12 Modbus con-
nectors (see fig. 6). OJ Air2 Fan IO21 collects
• Norsk
all signals relating to the air handling unit (see
fig. 2). Both electrical and mechanical signals
• Dansk
and measurements are converted for data
transmission. Via a standard communication
protocol (RS-485 Modbus RTU), the signals are
sent to the controller, which manages alarms
and controls and regulates the air handling unit
(see fig. 10).
Typical signals sent between the controller or
BMS system and the air handling unit are con-
cerning inlet temperature, exhaust temperature,
filter guard, differential pressure and flow guard
on inlet fan, damper motor for inlet air, damper
motor for exhaust air, 0-10 V DC speed signal
from frequency converter for fans, alarm signal
from frequency converter and operating signal
to fan frequency converter.
OJ Air2 Fan IO21 collects all these electrical
and mechanical signals and transmits them via
RS-485 Modbus RTU to the Master or BMS
system.
ENCLOSURE RATING
In order to meet IP54 rating, tubes must be
attached to all tube connectors and all rubber
membrane cable glands must be either used
or sealed with blanking plugs offering at least
IP54 ingress protection. This will ensure that
the enclosure as a minimum corresponds to the
IP54 rating of the product.
The enclosure can be easily opened and closed
using the practical one-hand-operated snap
locks. Dimensions (see fig. 3)
INSTALLATION
INSTALLATION
OJ Air2 Fan IO21 should be installed in a stra-
tegic, central location so that the wiring for the
input and output signals is as short as possible.
All that is needed to connect the module to a
Master, PLC or other controller type is simply
an RS-485 RTU Modbus communication cable
(see fig. 5).
OJ Air2 Fan IO21 should be attached to an
even surface by means of three screws (see
fig. 3). It can be fitted in any orientation without
adversely affecting accuracy.
OJ Air2 Fan IO21 has an approved enclosure
rating of IP54 and is equipped with four tube
connectors for attaching soft plastic tubes
used to measure pressure differential or over-/
underpressures. In addition, OJ Air2 Fan IO21
is equipped with five cable glands with rubber
membranes for cable entry.
The cover and lower edge of the enclosure are
equipped with a rubber membrane allowing
the Modbus cable (flat cable of type MPFK6S
or similar) to be fed into the enclosure beneath
the cover. When the cover is closed, the rubber
membrane is pressed tightly around the Mod-
bus cable, ensuring the enclosure meets IP54
requirements.
With its IP54 enclosure rating and temperature-
independent pressure transmitters, OJ Air2
© 2015 OJ Electronics A/S
Fan IO21 is designed to be fitted inside the air
handling unit. OJ Air2 Fan IO21 has an operat-
ing temperature range of -20/+40°C (transient
-30/+50°C).
Modbus connection
Modbus is connected to OJ Air2 Fan IO21 via
RJ12 connector "A" (see fig. 5). An OJ EC con-
troller or OJ frequency converter can be con-
nected directly to the OJ Air2 Fan IO21 module.
The EC controller or frequency converter is
connected to connector "B" (see fig. 5).
Connectors "C", "D", "E" and "F" (see figs 6 &
9) are used for connecting Direct Modbus con-
trolled damper or valve motors or for looping to
other Modbus equipment in the air handling unit.
OJ Air2 Fan IO21 is also equipped with screw
terminals for Modbus connection: terminals 1 &
2 (see fig. 1).
Supply voltage
A 24 V AC supply voltage for OJ Air2 Fan IO21
must be connected to terminals 13 and 14 (see
fig. 7 & 8). The total load on the OJ Air2 Fan
IO21 module may at most be 3500 mA.
OJ Air2 Fan IO21 cannot be powered via the
RJ12 connection.
Pressure tubes
The two pressure transducers marked P1 and
P2 should be connected with overpressure/
highest pressure on the + tube connector and
underpressure/lowest pressure on the ÷ tube
connector (see fig. 4).
The pressure tubes must be as short as pos-
sible and must be secured in position to prevent
vibration. To ensure optimum results, pressure
should be measured where there is least pos-
sible risk of turbulent flow, i.e. at the centre of
the ventilation duct.
The transmitters also function with only one
tube attached to the connectors (+ or -). How-
ever, unless the connectors face downwards,
tubes should always be fitted to all connectors
in order to maintain the enclosure rating.
If there is a risk of condensation forming in the
tubes, OJ Air2 Fan IO21 must be positioned in
such a way that condensate cannot flow back
into the pressure transducer.
The measuring range is 0-2500 Pa.
Pressure tube connection is illustrated in fig. 4.
Temperature inputs
OJ Air2 Fan IO21 is equipped with two sensor
inputs for PT1000 sensors (1000 Ω @ 0°C).
Sensor 1 should be connected to the "Temp. 1"
input on terminals 10 & 11. Sensor 2 should be
connected to the "Temp. 2" input on terminals
11 & 12.
The measuring range of the sensors is -30°C
to +60°C. Electrical connections are illustrated
in fig. 8.
Digital input
OJ Air2 Fan IO21 is equipped with one
potential-free digital input which can be used,
for example, for monitoring alarms from a fre-
quency converter. The potential-free signal from
the frequency converter should be connected to
the "Alarm IN" input on terminals 8 & 9. Electri-
cal connections are illustrated in fig. 8.
Digital output
OJ Air2 Fan IO21 is equipped with one
potential-free digital relay output which can be
used, for example, to start and stop a frequency
1