Parker IQAN-XS2 User manual

IQAN-XS2
Instruction book
Publ no HY33-8386-IB/UK
Edition 2015-12-10

ii
Contents
Instruction book, IQAN-XS2
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Overview of relevant documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Read This . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3 Product description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
IQAN-XS2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Internal diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
CAN-bus interruption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Current check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Emergency stop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5 Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Mounting the module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Supply voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Addressing/terminating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Reference voltage, VREF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Voltage inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Digital inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Digital outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
7 Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Start-up procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
8 System Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
IQAN-XS2 Technical Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Appendix B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Error codes, messages and actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Appendix C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Dimensioning of the IQAN module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Appendix D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Failure Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

1
Warnings
1 Introduction
Instruction book, IQAN
1 Introduction
These instructions are to be used as a reference tool for the vehicle manufacturer’s
design, production, and service personnel.
The user of these instructions should have basic knowledge in the handling of
electronic equipment.
Warnings
Sections marked with a symbol in the left margin, must be read and understood by
everyone using the system, carrying out service work, or making changes to hardware
and software.
The different symbols used in this manual are defined below.
WARNING
Sections labeled WARNING with a caution symbol in the left margin, indicate that a
hazardous situation exists. We use warnings, marked with the warning symbol, in two
ways.
• As a strong recommendation about work practices when using the product in the
machine (e.g. routines when updating an application). This use is common to the
term 'hazardous situation', that a person is exposed to a hazard.
• As a way of pointing out important information for the machine designer that in
some way relates to safety. This includes the design of the physical machine, and
also the application program being developed for the control system.
Not all document sections that contain information about safety are marked with a
warning symbol (there would be warnings everywhere). Failure to comply with the
recommendations can cause unintentional, and unexpected behavior of the control
system. This can potentially cause death, serious injury or property damage.
NOTICE
Sections labeled NOTICE with a notice symbol in the left margin, indicate there is
important information about the product. Ignoring this could result in less than optimal
performance, or damage to the product.
Contact the manufacturer if there is anything you are not sure about or if you have any
questions regarding the product and its handling or maintenance.
The term "manufacturer" refers to Parker Hannifin Corporation.

2
Overview of relevant documentation
1 Introduction
Instruction book, IQAN
Overview of relevant documentation
The following publications are relevant for users of this product.
The main documentation contains information that is not found elsewhere.
The additional documentation contains product information in a compact format, for
details on the information found in those documents, consult this manual.
The IQAN module documentation system.
Compact
Documentation
Main
Documentation
IQANdesign/
IQANrun
User Manuals
IQAN module
Instruction Book
HY33-8nnn-IB
IQAN module
Catalogue Datasheet
HY33-8nnn
IQAN module
Installation Sheet
HY33-8nnn-IS
IQAN module
Electrical Schematic
HY33-8nnn-ES
Mounting and Maintenance
Instruction Book
HY33-8327-IB

3
Read This
2 Precautions
Instruction book, IQAN
2 Precautions
Work on the hydraulics control electronics may only be carried out by trained
personnel who are well-acquainted with the control system, the machine and its safety
regulations.
WARNING
Make sure that you have sufficient knowledge before designing, modifiying or
servicing the control system.
Read the relevant sections of this document before conducting any work on the control
system.
WARNING
This product is not field repairable.
NOTICE
As much as possible of the welding work on the chassis should be done before the
installation of the system. If welding has to be done afterwards, the electrical
connections on the system must be disconnected from other equipment. The negative
cable must always be disconnected from the battery before disconnecting the positive
cable. The ground wire of the welder shall be positioned as close as possible to the
place of the welding. The cables on the welding unit shall never be placed near the
electrical wires of the control system.
Read This
Design of control system
WARNING
Risk of injury may be introduced by design of control system!
This product is designed to control hydraulic outputs. The control application must be
designed using basic safety principles so that unintentional movement is avoided.
The machine must be equipped with an emergency stop that stops all movement. Please
refer to section "Supply voltage".
Before you start
Read this document.
Read the IQANdesign software user manual section on 'application safety'.

4
Read This
2 Precautions
Instruction book, IQAN
Start-up, maintenance, and diagnostics
For all personnel carrying out installation, commissioning, maintenance or
troubleshooting.
WARNING
Work on the hydraulics control electronics may only be carried out by trained
personnel who are well-acquainted with the control system, the machine and its safety
regulations.
Before you start,
Read section "Start-up".
Additional information for service
Mounting and maintenance instruction book.
Additional information for diagnosing the system
Read section "System diagnostics", and see "Appendix B", in this document.
Use the IQANrun software user manual as a reference.

5
IQAN-XS2
3 Product description
Instruction book, IQAN- XS2
3 Product description
IQAN-XS2
The IQAN-XS2 is a flexible expansion module designed for controlling hydraulic
systems in vehicles and machinery, using 12/24 Vdc power supply.
The IQAN-XS2 module.
I/O overview
Inputs
The IQAN-XS2 module has eight (8) voltage inputs VIN-A thru VIN-H for connection
of 0-5 Vdc signals. The inputs may be configured as digital inputs DIN-A thru DIN-H.
Voltage inputs and digital inputs share positions, see below.
(8) Voltage inputs VIN-A, VIN-B, VIN-C, VIN-D.....VIN-H
or
(8) Digital inputs DIN-A, DIN-B.....DIN-H use positions VIN-A thru VIN-H.
+BAT ADDR-H
ADDR-L
CAN-H
CAN-L
PORT 1
PORT 2
-BAT
+VREF
-VREF
PORT 0
XS2

6
IQAN-XS2
3 Product description
Instruction book, IQAN- XS2
Digital inputs and outputs
The XS2 module has six (6) digital outputs for controlling on/off valves and twelve
(12) on/off intputs for switch inputs.
High power On/Off outputs
The XS2 module has six (6) on/off outputs that are high-side power outputs.
CAN related functions
The master uses the CAN-bus (CAN = Controller Area Network) to communicate with
the modules. The CAN-bus is a robust communication protocol that is widely used and
well proven within the automotive industry.
(6) on/off outputs, DOUT-G thru DOUT-L
(12) on/off inputs, DIN-I thru DIN-T.
(6) On/off outputs, DOUT-A thru DOUT-F

7
Internal diagnostics
4 Safety
Instruction book, IQAN
4 Safety
Internal diagnostics
The module performs a number of self-checks that improve safety. Checks include
monitoring of voltage supplies, checksums on memory and a watchdog that monitors
software execution. The module is using a real time operating system which supervises
software execution.
If a critical error is detected, the module is stopped, with CAN-bus and outputs off.
CAN-bus interruption
The IQAN modules communicate on a CAN-bus. Both the master module and
expansion modules check for any interruptions in CAN-bus communication. If an error
occurs the master will use zero or an application defined error value for the module
inputs, and the module outputs will be off.
The error will be presented on the master/display module, if there is one, and with a
related blink code on the IQAN module status LEDs.
Current check
For modules with proportional outputs, when used in current mode a current check is
performed. If an error is detected, this will be indicated on the master module, and the
output will shut off.
The module can detect open-circuit, short-circuit to +BAT/-BAT or short-circuit to
other proportional output and return pins.
Emergency stop
WARNING
Risk of injury!
The emergency stop must disconnect the power supply to the module; do not connect
the emergency stop as a signal input only.
The emergency stop must be installed so that the risk of reverse feed of the module is
avoided, see section "Supply voltage".

8
Mounting the module
5 Mounting
Instruction book, IQAN
5 Mounting
Mounting the module
The IQAN module should be mounted according to the following instructions:
• Locate the module eliminating the risk forthe cabling to be folded, crushed or dam-
aged in any way. Ensure the cabling cannot pull, twist or induce sideload on the con-
nector.
• Locate the module so that severe physicalimpact is avoided, e.g impact from falling
objects or the module being used as a step.
• Locate the module so thatair can circulat to eliminate excess heat. Ensure that no
external heat, e.g. from the engine or heater, is transferred to the module.
• Locate the module to protect it from high pressure washing or similar.
• Locate the module so that the cable connector is facing down .
• Locate the module so that the LEDs are visible.
Non approved placing.
NOTICE
The IQAN module must not be placed in any marine related or similar continuously
damp, salt-spray environment without external protection.
Assembling of the ID-Tag
The ID-Tag will be placed in the connector in order to address/ terminate the module.
For IQAN master modules, the use of an ID-tag is application dependant. All IQAN
expansion modules require an ID-tag, ref section "Addressing/terminating".
The ID-Tag will be mounted under the connector casing. Bend the ID-Tag’s wires
toward the opposite side of where the other wires enter the connector.
Assembling of the Id-Tag.

9
6 Installation
Instruction book, IQAN- XS2
6 Installation
Connector C1
Connector pin assignments
Connector kit Parker no. 5031063
Housing Amp no. 1-963226-1
Casing Amp no. 0-965643-1
Plane sealing, 42 p installed in module
Pin types* Amp no. 963711-2 (MT) Amp no. 929938-1 (JPT)
Cables 0,75-1,0 mm² (MT) 1,5-2,5 mm² (JPT)
Seals Amp no. 963530-1 (MT) Amp no. 828905-1 (JPT)
Plugs (empty pos.) Amp no. 963531-1 (MT) Amp no. 828922 (JPT)
IQAN crimping tool ref-
erences
Blue handle, pos. A
use blue extraction tool
Red handle, pos. B
use yellow extraction tool
IQAN tool kit Parker no. 5031061
Logical
Symbol
Pin
No.
(I)nput or
(O)utput
Function description
and/or Signal name(s)
+BAT 28-Power supply, positive.
-BAT 15 -Power supply, negative ground
+VREF 42 -Voltage reference for external sensors. Sourcing +5V.
-VREF 29 -Voltage reference for external sensors. Return (0V).
ADDR-H 1 - High side to address tag. Sourcing +5V.
ADDR-L 14 -Low side to address tag. Return (0V).
CAN-H 26
27
-
-
CAN high voltage bus line, will be HIGH in dominant state.
CAN-L 40
41
-
-
CAN low voltage bus line, will be LOW in dominant state.
*= The connector contains two types
of terminals; MT (Micro Timer) and
JPT (Junior Power Timer).
42
28
14
29
15
1
+BAT ADDR-H
ADDR-L
CAN-H
CAN-L
PORT 1
PORT 2
-BAT
+VREF
-VREF
PORT 0
XS2

10
6 Installation
Instruction book, IQAN- XS2
Shaded positions are Junior Power Timer pins. Unshaded positions are Micro Timer II pins. See above for wire, seal, pin
number and crimping tool information. The IQAN tool kit is found in the "IQAN accessories" datasheet.
Logical
Symbol
Pin
No.
(I)nput or
(O)utput
Function description
and/or Signal name(s)
P0
P0.0
P0.1
P0.2
P0.3
P0.4
P0.5
P0.6
P0.7
10
11
12
13
24
25
38
39
I
I
I
I
I
I
I
I
P0 is an 8pin input port with alternate functions on four inputs.
VIN DIN
VIN-A DIN-A
VIN-B DIN-B
VIN-C DIN-C
VIN-D DIN-D
VIN-E DIN-E
VIN-F DIN-F
VIN-G DIN-G
VIN-H DIN-H
Note: DIN-A to DIN-H have high impedance inputs (62K Ohm).
P1
P1.0
P1.1
P1.2
P1.3
P1.4
P1.5
8
9
22
23
36
37
O
O
O
O
O
O
P1 is an 6 pin output port.
DOUT
DOUT-A
DOUT-B
DOUT-C
DOUT-D
DOUT-E
DOUT-F
P2
P2.0
P2.1
P2.2
P2.3
P2.4
P2.5
P2.6
P2.7
P2.8
P2.9
P2.10
P2.11
P2.12
P2.13
P2.14
P2.15
P2.16
P2.17
2
16
30
3
17
31
4
18
32
5
19
33
6
20
34
7
21
35
O
O/I
O/I
O
O/I
O/I
O
O/I
O/I
O
O/I
O/I
O
O/I
O/I
O
O/I
O/I
P2 is an 18pin input/output port.
DIN DOUT
-DOUT-G
DIN-I -
DIN-J -
-DOUT-H
DIN-K -
DIN-L -
-DOUT-I
DIN-M -
DIN-N -
-DOUT-J
DIN-O -
DIN-P -
-DOUT-K
DIN-Q -
DIN-R -
-DOUT-L
DIN-S -
DIN-T -
Notes:
DIN-I to DIN-T are equipped with clamping diode, risk for ’backending’.See section
"Connecting switches to the digital inputs"

11
Supply voltage
Instruction book, IQAN
Supply voltage
Before any installation of the IQAN system can take place, make sure the ignition lock
is turned off and the battery is disconnected.
Emergency stop
Make sure an Emergency Stop disconnecting the power supply, is easily accessible at
any time. The figure below shows how to connect the emergency stop.
Connecting of Supply Voltage
The supply voltage, should be within the operating interval, see Appendix A. Connect
the supply voltage to +BAT and -BAT. Protect the module by using a fuse. For
recommended fuse level, see Appendix A.
RTC supply
IQAN master modules have a clock that is used for date/time stamping when logging
data. The real time clock, +RTC, requires a separate positive power connection.
Connect the supply voltage to +RTC through a 1.5K ohm resistor. The resistor should
be as close to the battery as possible for safety.
IQAN expansion modules do not have +RTC.
WARNING
Risk of injury!
To reduce the risk for uncontrolled supply of an IQAN master module, i.e., a short
circuit between the +RTC cable and +BAT, a resistor must be connected between the
battery and the +RTC input. This is important as this line is not controlled by an
emergency stop.
The resistor should be placed close to the battery, as the ’protected’ part is the cable
between the resistor and the unit.
This will prevent the +RTC wire from powering up the unit if shorted to +BAT.
Connecting the emergency stop and voltage supply.
NOTICE
Do not use the chassis as the negative terminal.
Polarity reversal
The module is protected against power supply polarity reversal and over-voltage,
provided an external fuse is being used.
If this fuse is not used, polarity reversal can damage the unit.
+-
Emergency Stop
+BAT
Fuse
-BAT
*
* Symbol for disconnecting
switch for battery, ignition
lock and other fuses.
+RTC (if master unit)
IQAN module
1.5 k

12
Addressing/terminating
Instruction book, IQAN
Addressing/terminating
Addressing
Each IQAN expansion module will have a specific address, enabling the master module
to communicate with the modules through the CAN-bus. When operating, the system
distinguishes between different modules by first verifying the module type and
secondly, through the modules having unique addresses.
The maximum number of similar modules in a system is four or eight depending on the
master module, denoted in the first case as addresses 0, 1, 2, 3 respectively. In order to
assign any IQAN module a unique CAN-address, an ID-Tag will have to be connected
to the positions ADDR-H and ADDR-L.
Connecting of Id-Tag.
Terminating
To eliminate interference in the communications through the CAN-bus, the CAN-bus
must be terminated at both ends. By default, if no ID-tag is installed in an IQAN
master, it will be terminated internally to be the Bus master and will have no special
configuration.
When an IQAN expansion module is located at the end of the CAN-bus, then you
would use an ID-tag having a combined addressing and terminating function. This is
denoted with a "T" for terminating, after the appropriate address such as; 0T, 1T, 2T...
etc. In the application, the same address value as the non-terminated ID-Tag with
equivalent number will be transferred to the application.
Selecting appropriate ID-Tag
• Check the address number of themodule assigned in the application.
• If the module is located at the end ofthe CAN-bus, then select the appropriate ID-
Tag denoted with a "T".
NOTICE
The CAN-bus must not be terminated at the module using an external regular
terminating resistor, due to the fact that terminating is made from within the module by
default or in conjunction with the ID-Tag.
EXAMPLE
If having an expansion module with address 0, the system will denote this one as
[module type]-A0, The letter "A" in the example refers to CAN-bus A.
ID-Tag
ADDR-L
ADDR-H
IQAN module

13
Reference voltage, VREF
Instruction book, IQAN
Reference voltage, VREF
The IQAN module is internally equipped with a voltage regulator to generate the
reference voltage VREF. The standard reference voltage will feed different kinds of
sensors and potentiometers.
VREF positions.
NOTICE
It is strongly recommended to use the module’s -VREF and +VREF to all sensors and
potentiometers that are connected to the module inputs. This will reduce bad
measurement based on potential fault (i.e. different ground points for other supplies in
relation to the IQAN module ground, -BAT).
Maximum load for the VREF is different according to 12/24 Vdc power supply, see
"Appendix A".
-VREF
+VREF
IQAN module

14
Voltage inputs
Instruction book, IQAN
Voltage inputs
Connecting sensors to the voltage inputs
The sensor signal range must be 0-5 Vdc. To detect signal errors such as short circuits
or interruptions the active signal range be within 0.5-4.5 Vdc.
Active signal range.
The current consumption related to the voltage input is negligible.
The positive terminal of the sensor is connected to the +VREF position and the
corresponding negative terminal to the -VREF position. The sensor signal is connected
to appropriate VIN position.
NOTICE
The negative terminal of the sensor must not be connected to the chassis.
Maximum load for VREF position: see Appendix A.
Connecting other 3 wire sensors
The same type of connection shown for potentiometers is used for other 3 wire sensors
supplied with power from the regulated 5VDC supply, VREF. This includes active
temperature sensor IQAN-ST, pressure sensor IQAN-SP and Hall-effect levers IQAN-
LST or IQAN-LSL.
EXAMPLE
Connect the positive and negative terminals of the position sensor to +VREF,
and -VREF, respectively. Then connect the sensor signal to VIN-X.
Connecting VREF and sensor signal VIN-X.
0
5
[V]
Active signal range
Error detection range
Error detection range
t
-VREF
+VREF
VIN-X
Position Sensor
IQAN module

15
Voltage inputs
Instruction book, IQAN
Connecting a 2-wire temperature sensor to voltage in
When you connect a PTC (positive temperature coefficient) temperature sensor you
may need to use a pull up resistor on the input signal. Please check the technical data
for your specific temperature sensor.
Connecting switches to the voltage inputs using VREF
Switches could be connected to the voltage inputs, to create a digital on/off signal. The
switches should be connected to +VREF and VIN/DIN respectively for 5V signal. The
current consumption for the input is negligible.
NOTICE
Maximum load for VREF position, see "Appendix A".
EXAMPLE
Connect the negative terminal of the temperature sensor to -VREF, and the signal to
VIN-X. The pull up resistor will be connected between VIN-X, and +VREF.
Connecting -VREF and temperature sensor signal VIN-X.
The pull up resistor value for a R25=2000 PTC sensor is 4,7 K
EXAMPLE
Connect the positive and negative terminals of the switch to +VREF, and VIN-X,
respectively.
Connecting a switch to VIN-X and VREF.
-VREF
VIN-X
+VREF
IQAN module
Sensor
pull up
VIN/DIN-X
+VREF
IQAN module
switch

16
Voltage inputs
Instruction book, IQAN
Connecting switches to the voltage inputs using +BAT
It is recommended to connect system voltage +BAT to the input through a switch in
order to reserve 5Vdc VREF for sensors and potentiometers.
EXAMPLE
Connect the positive and negative terminals of the switch to supply or the unit’s
+BAT, and DIN-X, respectively.
Connecting a switch to DIN-X and +BAT.
+BAT
DIN-X
IQAN module
switch

17
Digital inputs
Instruction book, IQAN
Digital inputs
DIN that share pins with VIN
These digital inputs share pins with the module voltage inputs and have high
impedance characteristics. The preceding switch examples apply to these inputs.
DIN that share pins with CRET
These digital inputs share pins with the return pins of the proportional output channels,
e.g. CRET and PWMRET. These pins have an internal power clamping diode. If used
as inputs they must be connected in a way that prevents ’backending’, that is, supplying
power to the module from a source other than its power pin (+BAT).
Carefully read the following section for more information.
Connecting switches to the digital inputs
When connecting switches to the digital inputs, DIN, that share pins with CRET, extra
precautions should be taken.
WARNING
The DIN that share pins with the CRET positions of the proportional outputs have a
possibility of ’backending’ the IQAN module when using those pins as digital inputs.
The internal circuitry has power clamping diodes between CRET pins and the internal
power supply. This arrangement creates a risk of inadvertently supplying power to the
unit.
You can safely connect using +VREF for the supply, as shown in the preceding
"Connecting switches to the voltage inputs" example.
If you would like to preserve +VREF for sensors and joysticks, then there are two
additional methods:
1 The switches could be powered by one of the module’s DOUT pins.
EXAMPLE
Connect the supply of the switch to DOUT-X, and the signal to DIN-X , respectively.
Connecting a switch to DOUT-X and DIN-X.
DIN-X
DOUT-X
IQAN module
switch

18
Digital inputs
Instruction book, IQAN
2 The switch supply could be connected through a high impedance resistor.
WARNING
Do not exceed 35Kohm for 12 Vdc systems and 50Kohm for 24 Vdc systems!
The DIN signal will not be detected by the module.
Remember that these flexible I/O pins must be configured in pairs of the same type.
EXAMPLE
Connect the supply of the switch to +BAT through a high impedance resistor, and
the signal to DIN-X , respectively.
Connecting a switch to DIN-X and supply through a resistor.
Switch
DIN-X, (shares RET pin)
Resistor
IQAN module
+BAT