Micronor MR430 Series User manual

© COPYRIGHT 2018, MICRONOR INC.
CAMARILLO, CALIFORNIA
UNITED STATES OF AMERICA
MR430 Series
ZapFREE®Fiber Optic
Absolute Encoder System
Instruction Manual
Doc No: 98-0430-11
Revision A3 dated 17-August-2018
MICRONOR INC.
900 Calle Plano, Suite K
Camarillo, CA 93012 USA
PH [phone]
FX [phone]
[e-mail]
www.micronor.com
For Support in Europe:
MICRONOR AG
Pumpwerkstrasse 32
CH-8105 Regensdorf
Switzerland
PH [phone]
FX [phone]
[e-mail]
www.micronor.com
Notice of Proprietary Rights
The design concepts and engineering details embodied in this manual, which are the property of
MICRONOR INC., are to be maintained in strict confidence; no element or detail of this manual is to be
spuriously used, nor disclosed, without the express written permission of MICRONOR INC. All rights are
reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in
any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior
written permission from MICRONOR INC.

MICRONOR INC.
MR430 Fiber Optic Position Sensor System
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Revision History
Revision
Date
Notes
A
8-March-2018
Initial Release
A1
21-June-2018
Product release
A2
11-July-2018
Added MR431 sensor diagrams
A3
17-Aug-2018
Added System Loss Budget to MR430 Controller specifications

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MR430 Fiber Optic Position Sensor System
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Table of Contents
1. Product Description ............................................................................................. 5
1.1 Position Sensor Background .........................................................................................5
1.2 Fiber Optic Position Sensor ..........................................................................................5
1.3 Features.........................................................................................................................6
2. Initial Preparation .................................................................................................7
2.1 Unpacking and Inspection ............................................................................................7
2.2 Damage in Shipment ....................................................................................................7
2.3 Standard Contents ........................................................................................................7
3. Installation and Operation.................................................................................... 8
3.1 Mounting the Sensor Unit .............................................................................................8
3.2 Mounting the Controller Unit........................................................................................9
3.3 USB (J2) and RS485/SSI Interface Connections (J3) ...................................................11
3.4 Optical Connection .....................................................................................................12
3.5 Blink Status and Error Codes ......................................................................................12
3.6 System Start-Up Without PC Computer .....................................................................13
3.7 Functional System Overview.......................................................................................14
3.8 Turn-Counter and Turn-Counter Size..........................................................................16
3.9 Multi-Turn Operation ..................................................................................................17
3.10 Battery Backup for Multi-Turn Operation ...................................................................17
3.11 SSI Interface ................................................................................................................18
3.12 Voltage Output ...........................................................................................................20
3.13 Isolated Current Output (4-20mA) ..............................................................................22
3.14 Digital Set Point ..........................................................................................................23
4. Serial Communication – Modbus ....................................................................... 25
4.1 USB-Serial Emulator ....................................................................................................25
4.2 Serial Interface Specification.......................................................................................26
4.3 Physical Connection for Modbus operation ...............................................................26
4.4 Serial Bus Termination Resistor...................................................................................27
4.5 MODBUS Communications Protocol ..........................................................................27
5. MR430 - Error Handling and Troubleshooting.................................................... 33
5.1 Explanation of Status and Error Handling...................................................................33
5.2 Explanation of Status and Error Indication .................................................................33
5.3 Reading the Error Counters ........................................................................................38
5.4 About Statistical Read Error Determination................................................................38
5.5 Warranty Information ..................................................................................................40
6. Specifications ..................................................................................................... 41
6.1 MR430 Controller Specification ..................................................................................41
6.2 MR431 Sensor Specifications ......................................................................................42

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MR430 Fiber Optic Position Sensor System
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7. ZapView®-MR480 Software ............................................................................... 43
8. MR430 Theory of Operation............................................................................... 43
9. Mechanical Reference Drawings......................................................................... 44
9.1 MR430-1 Controller.....................................................................................................44
9.2 MR431 Sensor .............................................................................................................44
9.3 MR439 M-POF Cabling...............................................................................................44
List of Figures
Figure 1. Micronor MR430 Fiber Optic Position Sensor System .................................................5
Figure 2. Three Methods of Mounting MR431 Sensor – (a) Synchro Mount with Clamps, (b) Synchro Mount
with Flat Washers, and (c) Face Mount. ...............................................................................8
Figure 3. Mounting MR430 Controller on DIN Rail .....................................................................9
Figure 4. Connections to MR430-1 Controller...........................................................................10
Figure 5. Location of RS485/Modbus RTU, SSI and USB Connections .....................................11
Figure 6. J3-Connector Pin Assignments...................................................................................11
Figure 7. Plug for J3 Connector.................................................................................................11
Figure 8. Location of Recessed Home Button ...........................................................................13
Figure 9. Block Diagram of MR430 System ...............................................................................14
Figure 10. Suggested Battery Backup Circuit............................................................................17
Figure 11. SSI Interface Connector – J3 (10 pin). ......................................................................18
Figure 12. SSI Single Transmission Timing ................................................................................19
Figure 13. Mode 1 Voltage Output ...........................................................................................20
Figure 14. Mode 2 Voltage Output ...........................................................................................20
Figure 15. Mode 3 Voltage Output ...........................................................................................21
Figure 16. Analog Output With An Oscillating Shaft Input .......................................................21
Figure 17. Isolated 4-20mA Connection...................................................................................22
Figure 18. Mode 1 Current Output............................................................................................22
Figure 19. Mode 2 Current Output............................................................................................23
Figure 20. Block Diagram of the Fiber Optic Position Sensor System ......................................43
List of Tables
Table 1. Table of Error Codes....................................................................................................35

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MR430 Fiber Optic Position Sensor System
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1. Product Description
1.1 Position Sensor Background
Position sensors are typically used to provide an absolute position from a mechanical moving device to a
controller unit. The position information is either used to measure a position or to close the servo loop for
an automatic positioning system. The key characteristics of an absolute position sensor are:
•Range
•Accuracy
•Resolution
•Time response of the actual position
1.2 Fiber Optic Position Sensor
The MR430 series fiber optic position sensor system is an innovative all-optical design immune to any
electro-magnetic interference such as lightning, radiation, magnetic fields and other harsh environmental
conditions. The fiber optic aspect of the sensor also makes it perfectly suited for sensing position at high
voltage power lines, within high magnetic fields (MRI) or explosive atmospheres. This innovative product
measures absolute angular position from 0° to 360° with 13-bit resolution and distances up to 100 feet.
Figure 1. Micronor MR430 Fiber Optic Position Sensor System
The sensor utilizes Plastic Optical Fiber for sensing the exact position of the sensor disk. There are two
fibers, the Transmit fiber sends a short light pulse of light at a wavelength of 645nm to the sensor. A unique
code on the sensing disk impresses the code image to the receiving imaging fiber. The controller analyzes
the code impressed on the Receiving fiber and determines the exact position. Since the sensor is
electrically passive, it can be deployed in EMI/RFI intense environment without being disturbed by such
interference.
The position signal is measured and updated at a rate of 1.2 kHz. The controller provides a host of
interface capabilities, including: scalable analog voltage and current outputs, digital SSI (Serial
Synchronous Interface) output, USB, and a Modbus compatible serial interface.

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MR430 Fiber Optic Position Sensor System
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1.3 Features
•Absolute Angular Position with 13-bit (8192) Resolution
•Multi-turn tracking to 12-bits (4096 turns)
•Immune to Electrical Interference
•Zero Emitted Electrical Radiation
•MRI Safe Sensor, Non-Metallic
•Transmission without Interference up to 30m (100 feet)
•Utilizes 1mm diameter POF fibers
•Multiple interfaces built-in into one unit
oSSI Interface
oModbus RTU via RS422/RS485 serial interface.
oUSB Interface
oTwo Scalable Analog Position Outputs (±10V and 4-20mA)
oOne Programmable Digital Set-Point
•User settable Zero Position
•External Zero Position input.
•Powers from +18V DC to +28VDC
•Low Energy consumption, < 1.5 Watts
•ZapView® Setup Software
•Small form factor Sensor (size 11)
•Ex classified “Inherently Safe, Simple Mechanical Device”, i.e. sensor can be installed in all manner
of hazardous location or combustible atmosphere – mines, gas, vapors or dust.

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MR430 Fiber Optic Position Sensor System
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2. Initial Preparation
2.1 Unpacking and Inspection
The unit was carefully inspected mechanically and electrically before shipment. When received, the
shipping carton should contain the following items listed below. Account for and inspect each item before
the carton is discarded. In the event of a damaged instrument, write or call your nearest MICRONOR office
in the U.S. A. Please retain the shipping container in case reshipment is required for any reason.
2.2 Damage in Shipment
If you receive a damaged instrument you should:
1. Report the damage to your shipper immediately.
2. Inform MICRONOR
3. Save all shipping cartons.
Failure to follow this procedure may affect your claim for compensation.
2.3 Standard Contents
MR431 Sensor:
•MR431 Sensor Device with customer-specified POF pigtail length
•Test Protocol Sheet
•Instruction Manual (this document, one soft copy supplied with each shipment)
MR430-1 SSI Controller Module:
•MR430-1 Controller Module
•Detachable Phoenix Terminal connector plugged into unit.
•ZapView®430 Instruction Manual (Paper Copy)
•MR232-3 USB Cable
•The following documents are supplied on a CDROM or USB Stick:
oMR430 ZapFree®Fiber Optic Absolute Encoder Instruction Manual (PDF file)
oZapView®430 Setup Software
oZapView®430 Instruction Manual
Available accessories (must be ordered separately):
•MR431A - set of 3, non-metallic synchro clamps and screws
•MR430-99-01 (J2) Breakout Cable for connection to SSI and RS485 interfaces
•MR498 cable assemblies (for extended links)
•MR498 inline mating adapters for use with MR498 extension assemblies

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MR430 Fiber Optic Position Sensor System
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3. Installation and Operation
3.1 Mounting the Sensor Unit
The MR431 sensor unit is a Size 11 standard servo mount configuration with Ø6mm shaft. Figure 2
illustrates 3 methods of mounting the sensor. Detailed mounting instructions and dimensions can be found
in the MR431 Reference Drawing in Section 9.2.
a) Synchro clamps (set of 3x clamps and screw available as Micronor P/N MR431-1101)
b) Flat washers
c) Face mount
Figure 2. Three Methods of Mounting MR431 Sensor – (a) Synchro Mount with Clamps, (b)
Synchro Mount with Flat Washers, and (c) Face Mount.
IMPORTANT NOTES
The sensor requires secure installation to meet published specifications.
No excessive force or load should be applied while installing.
The sensor should be mounted to a flat surface or bracket.
A flexible shaft coupling should be used when mounting to an external motor shaft.

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MR430 Fiber Optic Position Sensor System
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3.2 Mounting the Controller Unit
The controller unit mounts on standard 35mm DIN rail, or it can be screw mounted to a wall or cabinet.
•For DIN rail mounting, insert clip to the unit and then clip onto DIN rail by bending the clip tabs
toward of the enclosure.
•When screw mounting, remove clip from enclosure and use screws to affix clip to the wall and
then clip enclosure onto the plastic clip. Both mounting schemes are shown below.
IMPORTANT:
•The optical power emitted by the Controller is classified both Eye-Safe (Class 1) and Inherently
Safe (Ex op is).
•By design, the optoelectronic Controller must be installed in a non-hazardous, Safe Area.
Figure 3. Mounting MR430 Controller on DIN Rail

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MR430 Fiber Optic Position Sensor System
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The Sensor Controller requires
24V DC and consumes
approximately 60mA.
A number of interface options
exist:
Voltage and current outputs are
scalable using the ZapView®
software.
The 4-20mA current output is
isolated and requires an external
voltage source.
The Homing input requires a
18V to 24V logic or switch signal.
Figure 4. Connections to the MR430-1 Controller
The SSI interface usually connects to a PLC, servo drive unit or other position indicator. The SSI allows for
clock speeds of up to 250kHz and block read-out speeds up to 10kHz. Signals are available on connector
J3 which is shared with the Modbus interface signals.
The Modbus/RTU interface is available at connector J3. Controller units are slave devices and the device
address is programmable via this interface or the USB interface. Standard Baud rate is 57,600, 1 Stop Bit,
No Parity. The default Common Device Address is 235.
The USB interface is a serial FTDI Virtual Communications Port (VCP) serial emulator. It operates exactly
the same way and the protocol must be Modbus/RTU. Whenever the USB is connected and active, the
Modbus/Interface is disabled.
Electrical Connections to the Sensor Controller (J1)
1
+24V
Power Supply, 65mA typical
2
GND
3
Home
24V signal will set position to pre-defined value. (normally 0)
4
AUXin
24V signal. Reserved for future use.
5
GND
6
Set Point Out
5V Logic, goes Hi if a user-defined set point is reached.
7
Voltage Position Out
-10V to +10V, user defined scale based on position
8
GND
9
I (+)
4-20mA isolated current loop, user defined scale based on position,
user must provide a voltage source.
10
I (-)
Detachable Screw Terminal accepts 14 to 30AWG wires
Mating Terminal Connector: Phoenix P/N 1803659 (one supplied with unit)
Figure 4. Connections to MR430-1 Controller

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MR430 Fiber Optic Position Sensor System
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3.3 USB (J2) and RS485/SSI Interface Connections (J3)
Connector J2 provides the USB interface with Type B connection.
Connector J3 provides both RS485 and SSI interfaces.
Figure 5. Location of RS485/Modbus RTU, SSI and USB Connections
Figure 6. J3-Connector Pin Assignments
Default Baud rate is: 57600, 8 bit data, 1stop bit, no parity bit
Connector Plug: Hirose P/N 3240-10P-C(50)
Digikey P/N H11343-ND
Mouser P/N 798-324010PC50
Recommended Cable:
Tensility International P/N 30-00534
Digikey P/N T1355-5-ND
Micronor P/N MR430-99-01 (available separately) is a pre-assembled
pigtail assembly with 1m pigtail
RS485
Via J2
SSI
Via J2
(Optional)
MR430-99-01 Wire
Color Code
Pin
Function
Function
Color
1
+5V
+5V
Brown
2
RS422 – RCV- (input)
Red
3
RS422 – RCV+(input)
Orange
4
RS422 – TX- (output)
Yellow
5
RS422 – TX+(output)
Green
6
GND
GND
Blue
7
SSI-CLK-
Purple
8
SSI-CLK+
Grey
9
SSI-DAT-
White
10
SSI-DAT+
Black
NOTE: Pin 1 (+5V Power) can be used to power an RS232 to RS485 converter module.
Figure 7. Plug for J3 Connector

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MR430 Fiber Optic Position Sensor System
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3.4 Optical Connection
The system uses two POF fibers:
a.) Transmit fiber is a standard 1mm POF fiber. On controller
this fiber connects straight into the blue LED transmitter
receptacle. Push fiber all the way to the stop and then
gently lock the blue collar nut.
b.) Receive fiber is a plastic optical imaging fiber (POIF). On
the controller the end is terminated and has a high quality
polished finish. (do not scratch). The fiber is terminated
into an SMA connector with a key. Locate the key and
insert connector all the way and hand tighten the SMA
hex nut.
On the sensor end, the two POF fibers terminate into a special
purpose connector. This connector end is polished and must be
protected from scratches and contamination. This connector is a
service connector only, and it should be disconnected only when
mounting or servicing the sensor.
When sensor is disconnected cover sensor opening with a tape.
3.5 Blink Status and Error Codes
Status information is provided by a blinking PWR LED.
See Section 5 for more details regarding status and error codes.
Blinks
Code Description
Steady ON
System is ok. Shaft position within measuring range
1
Outside Range for Turn-Restore
2
Bad position signal.
-> Sensor may need to be “paired” to the controller box
3
No optical signal, i.e.Fiber disconnected
4
System Problem
The blinking LED status may be cleared by a momentary push on the Home/Reset button located
below the J1 connector.

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MR430 Fiber Optic Position Sensor System
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When the MR430 controller indicates an Error Blink Status, it is advisable to use the ZapView®430 software
to troubleshoot the problem. If not already installed on your computer, the current version of the software
can be downloaded from www.micronor.com.
3.6 System Start-Up Without PC Computer
It is recommended to use a PC (laptop) computer when making the MR430 Position Sensing System
operational. Micronor provides the ZapView® software for setting parameters and performing diagnostics
of the system. Checking the system after installation with ZapView® provides assurance that the installation
is complete and the system functions perfectly.
There may be instances where no PC is available. Installations that use only the analog or SSI outputs, do
not require specific programming on-site, especially if the MR430 controller was pre-configured for the
customer's application at the factory - or the customer is using the default settings.
Install the sensor as described above, connect the fiber optic lines, and apply 24V to the MR430 controller.
Rotate the sensor through at least one full revolution. If the power LED remains ON steady state, it means
that all tests internal were completed successfully and the system is ready to go.
All that is left to do is to set the Home (Zero) position. Bring the system to the desired Home position, and
activate the recessed Home button located below J1, as shown in the figure below.
Note:
In case of an error, the LED power light will blink a specific error code. The first press of the Home
button will acknowledge the error signal. The second press will secure the Home position. (Pressing the
switch twice will always Home the unit.)
Figure 8. Location of Recessed Home Button

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MR430 Fiber Optic Position Sensor System
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3.7 Functional System Overview
The MR430 system consists of an all optical, non-electrical, passive sensor (MR431) which is connected to
the MR430 Controller via a duplex POF and POIF fiber assembly.
The MR430 Controller constantly interrogates the sensor by sending a short optical pulse to the sensor.
The sensor impresses a code corresponding to the actual shaft position on to the imaging fiber. The
MR430 controller receives this optical image and through computational algorithms determines the
absolute shaft position. The system is a “Single Turn Absolute” position sensor. However, the controller
provides mechanism which enables the system to function quasi multi-turn position sensor.
Figure 9 provides a block diagram of the MR430 system and its user interfaces. The single-turn resolution
is 13 bits and there is also a 12-bit turn counter which keeps track of the full turns of the sensor while the
unit is powered up and the sensor is connected with the fiber optic link. Absolute single-turn position (13
bits) and turn counter (12 bits) combine to provide a 25-bit position signal. The user has the option to
mask the turn counter and thus limit the output to match the physical setup. If the sensor is only used to
measure a range over , let’s say, 5 turns then the user may limit the turn counter to 3bits providing a range
of maximum 8 turns until the output wraps around back to zero. Using the example above, the readout
would be limited to 16bits (0 to 65,535) to cover the position range of (3 turns times 8192 resolution per
turn) 24,575 counts
As the block diagram shows, the position signal is routed to all the various output interfaces built into the
unit and position information is available simultaneously.
Figure 9. Block Diagram of MR430 System
Absolute
Single turn 13-bit
Turn Mask
Voltage
Scaling
Mode
Current Scaling
Mode
RESET
Set-Point 1
SSI
pos_full
pos_rpr
t
J3J1
RS422/485
USB
Serial Interface
USB
Turn Counter
12bit
Zero Offset Full Position

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MR430 Fiber Optic Position Sensor System
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The Serial Interface conforms to the Modbus/RTU standard and is the main communications interface, ify
specifically for setup and configuration purposes. To simplify setup with a PC, a USB interface is also
provided.
The SSI interface (available at J3 on the bottom of the unit) is often used to interface with PLC controllers
and other automation equipment. This output toggles out fixed 25 bits and derives its information after
the turn-mask. Therefore maximum read-out values are restricted to what the turn-mask is configured to.
By definition, the SSI outputs only positive values. When the sensor rotates counter clockwise through
zero, the reading will go from 0 to the maximum possible readout value defined by the turn counter. If,
for example, the turn counter is set to 1, that means the maximum readout is 2(13+1)-1 = 16,383. The output
reads 2,1,0, 16,383.
The Current Output is a fully isolated 4-20mA loop powered output. It has three programmable operating
modes plus scaling over the full range of 25 bits. Digital to analog output resolution is 13 bits.
The Voltage Output provides voltage from -10V to +10V. It has four programmable operating modes plus
scaling over the full range of 25 bits. Digital to analog resolution is 12 bits plus sign.
One digital Set-Point output provides a Limit Switch-like behavior. This output can be programmed to turn
ON or OFF at a specific position with the full 25-bit range available. This output is a 5V logic level.
One external input is provided to Set the programmable Home position (usually zero). When this input
goes Hi, the position is set to the user programmable home position.
There is an Auxiliary input available for special custom functionality uses. Contact Micronor sales if a special
input function is required.
ZERO (HOME) Button Functionality
The ZERO or Homing button is located just below J1 connector.
•Manual Sensor and Controller Pairing (see Section 3.6)
•Set Current Position to ‘0’ or “HOME” location (see Section 3.6)
•Clear Error LED Codes (see Section 3.6)

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MR430 Fiber Optic Position Sensor System
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3.8 Turn-Counter and Turn-Counter Size
The MR430 controller keeps track of the turns using a 12bit counter. The 12 bit counter is combined with
the 13 bits of single-turn position information for a total of 25 bit position information. That arrangement
allows for up to 4096 turns with a resolution of 13 bits is a maximum position range of 33,554,432. Most
real world applications do not require this kind of measurement range. Therefore the user may want to
limit the number of turns that the sensor keeps track of. The size of the turn counter is controlled by the
user programmable ‘Turn Counter” variable. This number defines how many bits deep the turn counter is
counting until it rolls over back to zero. Please note there are no negative position numbers, all position
number are positive.
Example:
The application needs to measure a position over 12.4 turns. The next binary number is at 16 and therefore
the turn counter should be programmed to count to at least 16 turns. For this to take effect set the turn
counter variable to 4, because 24 equals 16. Only the first 4 bits of the turn counter are now activated.
12 11 10 9 8 7 6 5 4 3 2 1 024 23 22 21 20 19 18 17 16 15 14 13
13 bit single turn position
12 bit turn counter
2^ncounter length selector
13 bit single turn position
12 bit turn counter
4 bits
12 11 10 9 8 7 6 5 4 3 2 1 024 23 22 21 20 19 18 17 16 15 14 13

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MR430 Fiber Optic Position Sensor System
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3.9 Multi-Turn Operation
The MR430 controller accurately counts each turn while the system is powered and the remote sensor is
connected. Under these conditions multi-turn operation is possible.
If remote sensor is disconnected and the sensor position is moved past the zero point, then the turn
counter is no longer synchronized with the actual position. Similarly, if the power to the controller is lost,
then the sensor can no longer keep track of turns.
However, for a quasi multi-turn operation, the MR430 saves the last position, including the turns count,
just as the electrical power is removed from the unit. Often the application is such that when power is lost,
no further movement of the sensor is possible. Under these circumstances, the user may elect to have the
MR430 controller restore the turns upon power-on. To safeguard against erroneous position restoration,
the MR430 controller compares the new start-up single-turn position with the position saved at power
down. If that comparison falls within a user defined range then the turn counter is restored. Together with
the absolute single-turn position the actual multi-turn absolute position is retained in case of a power
outage.
Note
: User must decide if a quasi-Multi-Turn operation is feasible and appropriate.
3.10 Battery Backup for Multi-Turn Operation
The quasi multi-turn operation as described in the previous section is not fail-safe. A better method is to
use a Battery backup and keep the unit powered up even over prolonged power outages. The low power
consumption of only 60mA makes this feasible.
Figure 10. Suggested Battery Backup Circuit

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MR430 Fiber Optic Position Sensor System
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3.11 SSI Interface
Figure 11. SSI Interface Connector – J3 (10 pin).
The SSI interface is configured as Slave and the Master must supply the clock. The clock maybe in the
range from 25kHz to 250kHz. The user should also set the MR430 with the appropriate clock rate. This will
allow the MR430 to provide correct timing for repeat read' mode on the SSI bus. If not sure how to set the
SSI baud rate leave it at the lowest setting of 25k baud, this setting will work fine in most applications.
Reading position packets at higher than 4 kHz is not recommended as the update rate of the MR430 is
1.2kHz. Reading at higher intervals will not add more information.
Termination Resistor
For long link length and high clock rate it may be necessary to terminate the Clock line at the MR430 in
order to avoid reflective signal interference. The user must install that resistor external to the MR430. (For
OEM customers please consult MICRONOR as this resistor may be added inside the controller)

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SSI Single Transmission
The diagram in below illustrates a single data transmission using SSI protocol:
Figure 12. SSI Single Transmission Timing
The SSI is initially in the idle mode, where both the data and clock line are high. The transmission mode is
evoked when the master initiates a train of clock pulses. Once, the slave receives the beginning of the
clock signal (1), it automatically freezes its current data. With the first rising edge (2) of the clock sequence,
the MSB of the sensor’s value is transmitted and with consequent rising edges, the bits are sequentially
transmitted to the output. After the transmission of complete data word (3) (i.e. LSB is transmitted), and
an additional rising edge of the clock sets the clock line to go HIGH. The data line is set to low and remains
there for a period of time, tm, to recognize the transfer timeout. If a clock signal (data-output request) is
received within the time, tm, the same data as before will be transmitted again (multiple transmission).
The slave starts updating its value and the data line is set to HIGH (idle mode), if there are no clock pulses
within time, tm. This marks the end of single transmission of the data word. Once the slave receives a clock
signal at a time, tp ≥ tm, then the updated position value is frozen and the transmission of the value begins
as described earlier.
To set this timeout, use ZapView® software and select page: ‘SSI Interface”
MODBUS commands:
Address
Register
Description
0x138
0x139
Baud Rate SSI

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3.12 Voltage Output
The analog output voltage is derived from the position signal and maybe freely scaled by the user. There
are four distinct modes:
Mode 0: OFF, voltage is always 0
Mode 1: Single-turn 0V to +10V
Mode 2: Scalable 0V to +10V
Mode 3: Scalable -10V to +10V
Figure 13. Mode 1 Voltage Output
MODE 1 automatically sets the Scale to 8192. It outputs 0V when position is 0 and +10V when
position is 8191. Output wraps around back to 0V when one turn completes. This wrap around
occurs regardless of the Turn Mask setting.
Figure 14. Mode 2 Voltage Output
MODE 2 lets the user program the output voltage based on a scale value. The output is 0 when the position
is 0 and will reach +10V when the position reaches the scale value. The full 25-bit range is available for
scaling.
When setting this mode up the user should also take into account what should happen when the position
reaches maximum or minimum values. The MR430 system determines the wrap-around point based on
the available position range, which is based on the turn mask setting n. The Countmax is then 2n
The wrap point Pw is determined based on the formula above. Essentially, it is the midpoint between the
unused range.
Pw =(Countmax -Scale) + Scale
2