DYNAPAR HS35iQ User manual

See an example of how to connect the fault output of the HS35iQ encoder to a PLC with
example connection diagrams and necessary accessories.
How to Connect HS35iQ Encoder Fault Output to a PLC
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By Robert Cachro, Sr. R&D Engineer and Brad Stecker, Engineering Manager
Introduction
In this example the fault output from an HS35iQ encoder was connected to a Rockwell PLC. A simple single line
of ladder logic was used to read the fault line from the encoder and turn on an LED when a fault is present. The
LED is just an easy way to indicate the fault was successfully read from the encoder but other solutions such as
alerting maintenance are possible by utilizing the fault output function.
Hardware Setup
The following components were used to test this example:
•HS35iQPROGR81721R2 encoder with 2.2k load resistors
•L27ERM-QBFC1B PLC
•24V DC Power supply
•LED with current limiting resistor
The supply terminals for the PLC and the encoder were both connected to the same 24V DC power supply. The
24V power supply was also connected to the +V and COM0 connections on the “DC OUT” port included with the
PLC. The anode or positive side of the LED had a resistor connected in series to limit the current supplied from
the PLC output. The LED/resistor pair was connected to DC OUT 08 and COM. The fault outputfrom the encoder
was connected to DC IN 00. COM0 of “DC IN” was also tied to common (COM) of the PLC and encoder. See
the wiring diagram in Figure 1.
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Figure 1. Wiring diagram for example

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Software Setup
The routine written to read the fault output and turn on the LED is shown in Figure 2.
Figure 2. PLC software routine
An Examinine Off was used as the fault output is high during non-fault conditions and transitions to low when a
fault occurs. The routine simply reads the status of the fault output on DC IN 0 and will energize DC OUT 08
connected to the LED if a low condition is read.
Testing
After everything was connected properly, the program was downlaoded to the PLC and it was set to run mode.
To test proper functionality a cable fault was triggered by detaching the load resistor from one of the encoder
outputs (A/B/Z). The cable fault LED on the encoder transitions to RED at the same time the LED connected to
the PLC turns on (Figure 3). After the fault is corrected the cable fault LED on the encoder turns GREEN and
the LED on the PLC turns off (Figure 4).
Figure 3. PLC indicating active fault output

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Figure 4. PLC indicates inactive fault output
About Dynapar
Dynapar is an industry leading supplier of encoders, and resolvers. From small kit encoders to large mill-duty
tachometers, Dynapar has a strongmarket presence in a wide rangeof industries including steel, paper, elevator,
oil and gas, aerospace & defense, medical, material handling and industrial servo manufacturing. Dynapar offers
a broad array of encoders and resolvers through our well established Dynapar™, Hengstler™, NorthStar™and
Harowe™brands. Dynapar supports global customers with local sales and production locations in USA,
Germany, Slovakia, China, and Brazil.