turck EZ-track Q21D Series User manual

EZ-track®
Q21D Series Digital Output
Manual
Your Global Automation Partner

2 B1404 www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441
Contents
Chapter 1: Hardware Overview
Description of Q21D Digital Output ...................................................................................... 3
Dimension Drawing for Q21D Digital Output ............................................................................. 3
Chapter 2: Installing the Q21D
Mounting Instructions ................................................................................................... 4
Mounting the Magnet Assembly ......................................................................................... 4
Chapter 3: Q21D Overview
Control Pulse (CP) ....................................................................................................... 4
Variable Pulse (VP)....................................................................................................... 4
Recirculating ............................................................................................................ 4
RS (Start/Stop)........................................................................................................... 4
Q21D Wiring Connections ............................................................................................... 6
Troubleshooting......................................................................................................... 7
Specications for Q21D Digital Output ................................................................................... 8
Digital Prole Series Part Number Key .................................................................................... 9
Accessories.............................................................................................................. 10
Warning:
Disconnect power before servicing. The Q21D Digital Output contains no serviceable components. Consult Factory for
repair or replacement.

B1404 3
www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441 www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441
Chapter 1: Hardware Overview
Description of Q21D Digital Output
The Q21D with Digital Output is an accurate, auto-tuning, non-contact, linear displacement transducer in an economical,
low prole package. The transducer utilizes our eld proven magnetostrictive technology to give absolute position,
repeatable to .006% of the active sensing distance. The streamlined anodized aluminum extrusion houses the sensing
element and electronics. The magnet moves over the sensing element which determines the position and converts it to a
Digital output.
The Q21D LDT has auto-tuning capability, which is the ability to sense a magnet other than the standard slide magnet and
adjust its signal strength accordingly.
There is a diagnostic LED that is located at the connector end of the probe and provides visual status information regarding
the operation of the LDT. Green indicates proper or normal operation. Red indicates the loss of the magnetic signal or an LDT
failure. When the LDT is in the normal mode of operation, the LED will remain illuminated continuously.
Green: Magnet is present and within the active range.
Red: Fault, the LDT has lost its signal from the magnet or the magnet has moved into the Null or Dead zone.
Yellow: No external interrogation pulse detected.
The Q21D with Digital Output is a Linear Displacement Transducer. It provides a Control Pulse, Start/Stop or Variable Pulse
output signal that is proportional to the position of the slide magnet assembly along the length of the probe.
Dimension Drawing for the Q21D Digital Output
Note:
The part number on your LDT is a description of all the specic characteristics that make up your unit. This includes
what interface type it is, its output signal and range, the type of connector the unit uses, and stroke length (see page 9 for
part number key).
Floating Magnet
FM-Q21
The Q21D with Digital Output

4 B1404 www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441
Chapter 2: Installing the Q21D
Mounting Instructions
The Q21D Digital can be mounted vertically or horizontally using MB-Q21 mounting brackets. The mounting
brackets slide in the grooves on the lower part of the extrusion and clamp down when tightened. It is recommended
to use one mounting bracket on each end and every three feet in between.
Mounting the Magnet Assembly
Before mounting the magnet assembly, you should consider the following:
• Ferromagnetic material should not be placed closer than 1/4”from the LDT’s sensing surface. Failure to do so could cause
erratic operation. Non-ferrous materials, such as brass, copper, aluminum, non-magnetic stainless steel or plastics, can be
in direct contact with the magnet assembly and sensing surface without producing any adverse results.
• Make sure that the magnet is located within the LDT’s active stroke area. Captive magnet assemblies should be positioned
so that they can move freely over the entire area of the active stroke without binding or pushing on the extrusion.
Non-captive magnet assemblies should be situated so that the magnet is no further than 3/8”from the sensing surface at
any point in the oating magnet assembly’s movement.
• When using the Floating Magnet assembly (FM-Q21), the magnet should be installed within 3/8”of the sensing
surface. The magnet assembly should also be installed in such a manner that it remains an even distance from the
aluminum extrusion throughout the entire stroke. Improperly installed magnets can result in output signal non-linearity.
Chapter 3: Q21D Overview
CP (Control Pulse)
The Control Pulse signal interface of the Q21D digital output series is a dierential RS-422 output. The maximum cable length
for the dierential digital EZ-track is 1500 feet. To initiate a start pulse, an external device is used. This start pulse should
be a minimum of 1.0 microsecond in duration. After the start pulse is received, the Q21D will generate a stop pulse of 2.0
microseconds in duration. The time between the leading edge of the start pulse to the leading edge of the stop pulse is
proportional to the distance from the Null Zone to the Magnet. The order of these two pulses is illustrated in the Figure 3-1. To
wire the Q21D see Figure 3-7. For proper grounding information, see page 6, Q21D Wiring Connections.
Variable Pulse (VP)
The Variable Pulse signal interface of the Q21D digital output series is a pulse width modulated signal (RS-422). The maxi-
mum cable length for the dierential LDT’s is 1500 feet. This LDT can also be congured for external or internal interrogation.
External interrogation is when an external device connected to the LDT generates a start pulse. This start pulse should be a
minimum of 1.0 microsecond in duration. Within 50 nanoseconds after the leading edge of the start pulse has been received,
the LDT will generate an output pulse. The duration of the output pulse is proportional to the distance from the Null Zone to
the Magnet. The order of these two pulses is illustrated in Figure 3-2.
The Q21D Variable Pulse can also generate internal interrogations. This LDT will continually output pulse width modulated
signals. As with a Q21D Variable Pulse, using an external interrogation, the duration of this output pulse is proportional to the
distance from the Null Zone to the Magnet. This is illustrated in Figure 3-3. To wire the Q21D Variable Pulse, see Figure 3-7.
Recirculations
The method used to improve the resolution of a system using a digital LDT. The “on”time of a pulse width output is multiplied
by a specic factor (from 1-127). This multiplication provides more counting time for the counter in the customer’s electronics,
thus improving the resolution. The only disadvantage to the higher recirculating numbers is the time needed to
process the signal.
RS (Start/Stop)
The Start/Stop signal interface of the Q21D digital output series is dierential RS-422 output. The maximum cable length for
dierential LDT’s is 1500 feet. To initiate a start pulse, an external device is used. This start pulse should be a minimum of 1.0
microsecond in duration. Within 50 nanoseconds after the leading edge of the start pulse, the LDT will generate a start pulse
of 1.0 microsecond in duration. A stop pulse of 1.0 microsecond in duration will follow. The time it takes from the leading
edge of the start pulse to the leading edge of the stop pulse is proportional to the distance from the Null Zone to the Magnet.
The order of these two pulses is illustrated in Figure 3-4. To wire the Q21D Start/Stop signal, see Figure 3-7.

B1404 5
www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441 www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441
Chapter 3: Q21D Overview (continued)
Figure 3-1 Q21D CP
1 Microsecond (Recommended)
0.2 Microsecond (Minimum)
Time between pulses is proportional to distance
between magnet and null zone
Input (Start pulse)
Output (Stop pulse)
Figure 3-3 Q21D VPI with Internal Interrogation
Output pulse
Width of pulse is proportional to distance
between magnet and null zone
Low output varies depending on the
interrogation time and the position of
the magnet
Figure 3-2 Q21D VPE with External Interrogation
1 Microsecond (Recommended)
0.2 Microsecond (Minimum)
Width of pulse is proportional to distance
between magnet and null zone
Input (Interrogation)
Output pulse
Within 50 nanoseconds after interrogation
pulse width modulated output signal begins
Figure 3-4 Q21D RS
1 Microsecond (Recommended)
0.2 Microsecond (Minimum)
Input (Interrogation pulse)
Time between pulses is proportional to
distance between magnet and null zone
Output (Start pulse) Output (Stop pulse)
Within 50 nanoseconds after interrogation
pulse, start pulse begins

6 B1404 www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441
Q21D Wiring Connections
Once the LDT has been installed, wiring connections can be made. There are two groups of connections you will need to
make. They are as follows:
• Power Supply Connections (including ground and shield)
• LDT’s Input/Output Connections
Power Supply/Ground Connections
The Q21D standard cable is a 6-pin, 12 mm eurofast ® style Cordset (see Figure 3-6 thru 3-8). It has 6 conductors of 24
AWG, with an aluminum/polyester/aluminum foil with drain wire plus an overall braid of tinned copper shield. Outside
cable diameter is 0.20 inches. To reduce electrical noise, the shield must be properly used. Connect the cable’s shield to the
controller system GND.
Always observe proper grounding techniques such as single point grounding and isolating high voltage (i.e. 120/240 VAC)
from low voltage (13.5-30 VDC cables). Whenever possible, this cable should be run in conduit by itself. The power supply
common, the cable shield and a good earth ground should be connected together at the location of the power supply
common.
WARNING:
Do not route the LDT’s output cable near high voltage sources.
In order for the Q21D to operate properly, the LDT’s external power supply must provide a voltage between +13.5 to +30
VDC. The power supply must be rated at 150 mA minimum. The power supply should provide less than 1% ripple and 10%
regulations (the power supply should be dedicated to the LDT to prevent noise from external loads from aecting the
position readings.)
Single Ended
Power Supply
+13.5 to +30 VDC
+COM
Pin 1
(Brown)
Pin 3
(Blue)
Figure 3-5: Power Supply Wiring
Figure 3-7: Wiring Diagram (Cable Assembly) Figure 3-8: Wiring Colors
Figure 3-6: Pin-out
PIN-1 Brown
PIN-2 White
PIN-3 Blue
PIN-4 Black
PIN-5 Gray
PIN-6 Pink
POWER +
OUT+
COMMON
OUT -
INT -
INT +
Wire
Color RKC6T-*/S618 Pin-out
Brown 1 PWR+
White 2 OUT+
Blue 3 COMMON
Black 4 OUT
Gray 5 INT
Pink 6 INT+

B1404 7
www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441 www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441
Troubleshooting for Q21D Digital Output
Troubleshooting describes common problems that may occur when installing the LDT and oers possible solutions to these
problems. If, after troubleshooting the LDT, you are unable to resolve a problem, contact our application support department
at [phone].
General Checks
Make sure that the magnet is located within the LDT’s active stroke area. Captive magnet assemblies should be positioned so
that they can move freely over the entire area of the active stroke without binding or pushing on the extrusion. Non-captive
magnet assemblies should be situated so that the magnet is no further than 3/8”from the sensing surface at any point in the
oating magnet assembly’s movement
Note:
Ferromagnetic material (material readily magnetized) should be located no closer than 0.25”from the sensing surface of the
LDT. This includes mounting brackets, magnet spacers, magnet brackets, and mounting screws. Ferromagnetic material can
distort the magnetic eld, causing adverse operation or failure of the LDT.
Check all LDT wires for continuity and/or shorts. It is preferable that the cable between the LDT and the interface device be
one continuous run. If you are using a junction box, it is highly recommended that the splice junction box be free of AC and/
or DC transient-producing lines. The shield should be carried through the splice and terminated at the interface device end.
Power Supply Check
This section will help you to determine if your power supply is adequate for the LDT to operate properly, or if the LDT cable has a
short or open.
In order for the Q21D to operate properly, the external power supply must provide a level between 13.5 to 30 VDC. A power
supply providing voltage above this specied range may damage the LDT. A power supply providing power below this specied
range will not be sucient to power the LDT. When powering more than one LDT on a single power supply, remember that each
LDT requires 2.5 watts of power maximum. The amount of current draw will vary based on the input voltage used.
To calculate the current draw for a particular LDT, divide the LDT wattage by the input voltage. For example, 2.5 watts divided by
24 VDC equals 105 mA.
If your LDT is not operating properly, the LDT cable may have an open or short, or the power supply is not supplying sucient
power. To verify this, perform the following steps:
1. Turn the power supply OFF.
2. Remove the mating connector from the LDT.
3. Turn the power supply ON.
4. Using a digital voltmeter, check pins 3 (GND) and 1 (+) from the mating end of the cable for a level between
+13.5 and +30 VDC.
If reading is between 13.5 and 30 VDC, turn power supply OFF and go to Step 7. If reading is below 13.5 VDC, either your power
supply is not providing enough power or the LDT’s cable possibly has a short/open. Readings of no voltage or minimal voltage
(less than 5 volts) may be due to short/open in the cable. If reading is NOT between 13.5 and 30 VDC, go to Step 5. If reading is
above 30 VDC, adjust power supply or replace.
5. Turn the power supply OFF.
6. Check the continuity of the individual wires of the cable between the power supply and the LDTs. Check for continuity
from one end of the cable to the other. Also verify that no shorts exist between pins.
7. Reconnect the mating connector to the LDT.
8. Turn power supply ON.
9. Using a digital voltmeter, check the power supply’s “+” and “-” terminals for a voltage between 13.5 and 30 VDC.
Low voltage readings may indicate a power supply with a wattage (current) rating that is too low. (Each LDTs requires 2.5
watts.) If the cabling checks out in Step 6, and your voltage is below 13.5 VDC, check your power supply current rating. If
voltage is between 13.5 to 30 VDC and the LDT is still inoperative, contact factory.

8 B1404 www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441
Specications for Q21D Digital Output
General Specications
Null Zone 3.00”
Dead Zone 2.00”
Extrusion Assembly Anodized Aluminum with gasket seals, IP 67, IP 68 Optional
Connector 6 Pin, M12 eurofast®
Sensor Length 5”to 180”
Agency Approval CE
Shock & Vibration
Random Vibration MIL-STD 810E, 10Grms random, 20Hz - 2K Hz
Shock Tested to 40G
Electrical Specications
Input Voltage Unipolar 13.5 to 30 VDC
Current Draw 2.5 watts maximum
Nonlinearity +/- 0.05% of full stroke
Repeatability +/- 0.006% of full stroke
Hysteresis +/- 0.02% of full stroke
Operating Temperature -20° to 70° C
Storage Temperature -40° to 85° C
Update Time Controller Dependent
Specications are subject to change and are based on a typical 36”LDT.

B1404 9
www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441 www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441
Digital Prole Series Part Number Key
Part Number Key: Digital Prole Series
Note: In addition to the LDT, a typical system includes a magnet, mounting feet and cable (all sold separately).
¹⁾ Only Available with Output Mode 'VPI' or 'VPE'. Otherwise (Blank)
A Type
LT Linear Transducer
B Measuring Span
* Length of Measuring Span
C Units of Measurement
E Inches
D Housing Height
Q21D 21 mm
Q35D 35 mm
A B C D E F G H I
LT 40 E - Q21D - VPI - 001 - X3 - H1161 / S1661
E Output Mode
CP RS422, Control Pulse
RS RS422, Start/Stop Pulse
VPE Variable Pulse External Interrogations
VPI Variable Pulse Internal Interrogations
I Specials
(Blank) IP67
S1661 IP68
H Type of Connection
H1161 6-pin M12 eurofast® Connector
F Number of Recirculations ¹⁾
* 001 (Standard) to 127
G Number of LEDs
X3 3 Diagnostic LED's

10 B1404
www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441
Slide Magnet
SM-Q21 [A5600]
Slide Magnet with Slide Adapter
SA-Q21 [A0864]
Floating Magnet
FM-Q21 [A5500]
Control Arms
CA*E-Q21
Q21 Upside Down Brackets
UB-Q21 (2/bag) [A5500]
Q21 Mounting Brackets
MB-Q21 [A5700]
Rod Ends
RE-Q21 [A0865]
RBVA-M5
Angle Joint for M5 Thread,
Stainless Steel
ABVA-M5
Angle Joint for M5 Thread,
Stainless Steel
Accessories

B1404 11
www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441 www.turck.com • Phone: [phone] • Application Support: 1-800-544-7769 • Fax: [phone] • Turck Minneapolis, MN 55441

28 subsidiaries and over
60 representations worldwide!
www.turck.comB1404 B 10/15
©2015 by Turck Inc. All rights reserved. No part of the
publication may be reproduced without written permission.
Printed in USA