Applied DRDL User manual

Operating Instructions
Dual Range Torque Transducer
DRDL
DRDL-n
DRDL-w
English

Applied Measurements Ltd
appmeas.co.uk
[email protected]

1
Content
Important Advice..........................................................................................................................2
1. Introduction .............................................................................................................................3
2. Application ...............................................................................................................................3
3. Technical Details.......................................................................................................................4
3.1 Torque Shaft......................................................................................................................4
3.2 Case ...................................................................................................................................4
3.3. Measurement...................................................................................................................4
3.4 Disturbances and their Compensation ..............................................................................5
4. Operating conditions................................................................................................................5
4.1. Environment Temperature...............................................................................................5
4.2 Humidity and Dust.............................................................................................................5
4.3 Chemically Resistance .......................................................................................................5
4.4 Deposition .........................................................................................................................5
5. Mounting..................................................................................................................................6
5.1 Precautions at Assembly ...................................................................................................6
5.2 General Mounting Instructions .........................................................................................6
6. Measuring Chain ......................................................................................................................7
7. Connection ...............................................................................................................................7
7.1 Hints for Connection..........................................................................................................8
7.2 Connectors ........................................................................................................................8
7.3 Pinout of the Connector....................................................................................................8
7.4 Prolongation of Cable........................................................................................................9
7.5 Supply Voltage...................................................................................................................9
8. Pin Configuration ....................................................................................................................10
8.1 Standard-Measuring Cable AK12.4..................................................................................10
8.2 Robot cable AK12.5 ..........................................................................................................11
8.3 Thin cable AK12.2 ............................................................................................................12
9. Output....................................................................................................................................13
10. Recalibration ........................................................................................................................13
11. Disposal ................................................................................................................................13
12. Angle and speed measurement at high rotation speeds......................................................14
13. Technical Specifications ....................................................................................................... 16
13.1 Mechanical Dimensions.................................................................................................17
13.2 Mechanical Values and Load Limits...............................................................................18
Applied Measurements Ltd
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2
Important Advice
The torque transducers of type DRDL are suitable for applications in laboratories
(for example in testing equipment) as well as in industrial environment.
The torque transducer is not designed with the usual safety factor (2...20),
favoring high sensitivity instead.
Pay attention to the overload limit.
You have to protect users from danger of being hurt (metal cover etc.)
The torque transducer is not designed for explosion endangered areas.
Warranty is void if opened or disassembled.
The transducer must only be opened by authorized personnel.
Applied Measurements Ltd
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1. Introduction
The torque transducers have different shafts according to measurement range.
Torque transducers’ measurement unit is Nm.
2. Application
Torque transducers are able to measure clockwise as well as counter clockwise torque.
With clockwise torque the output is positive. The type label indicates the range of the
transducer.
The torque transducers measure static torque as precise as dynamic torque. Yet you have
to pay attention to the transducer’s signal rise time. It is indicated in the Data sheet.
The torque transducers are maintenance-free.
Handle the torque transducer with care, especially when transporting or mounting.
Because it can be damaged by hard shocks or by dropping to ground. Even a short peak
torque above the allowed overload capacity can damage the measure shaft. In cases
where this can happen you have to take precautions to avoid this.
The absolute maximum ratings regarding mechanical, thermal and electric parameters are
listed in the data sheet and must be observed in design, mounting and operating.
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3. Technical Details
3.1 Torque Shaft
The shaft is fixed in the chasing with two ball bearings.
To measure the torque it causes a proportional bending of the shaft (within the elastic
range) and this is measured with applied strain gages. The strain gages are connected as a
wheatstone bridge. Additional angle or speed measurement is optionally available. (See
the data sheet.)
3.2 Case
The housings of the torque transducers are made of high-strength aluminum, the surface
is hard anodized for protection. The torsion shaft has two bearings in the housing via deep
groove ball bearings. The mechanical attachment of the transducer is carried out using a
foot attachment. Evaluation electronics for torque and speed or angle of rotation are
mounted on the housing.
3.3. Measurement
The torque causes the bending of the shaft and the strain gages. The resistance of the
strain gages changes proportional to the change of their length. And this is converted into
an electrical signal that causes a frequency modulation. This modulated signal is
transmitted optically to an electronic circuit in the casing. There it is converted back to a
proportional analog output voltage. This output voltage has a separate ground that is
electrically separated from the transducer’s supply.
For speed and angle measurement the pulses of a code wheel are encoded to a square
wave signal. With option speed measurement the output is 60 pulses per revolution, with
option angle measurement two square wave signals are provided with an output of 360
pulses per revolution. While clockwise rotation the signal of channel A is approximately 90
degrees ahead of channel B.
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3.4 Disturbances and their Compensation
Avoid bending, axial and radial forces. When you have problems with this, use ETH
clutches.
To connect the transducer to a measurement unit you need a shielded cable.
The transducers are EMC-tested and are complying with EN 55011/03.91 (DIN VDE 0875-
11/07.92) respective prEN 50082-2/1993 (E DIN EN 50082-2/03.94).
4. Operating conditions
4.1. Environment Temperature
For best accuracy you have to meet the environment temperature specification. The
temperature should be constant or slowly changing. The specified temperature errors
apply only for changes less than 5 K/h. Radiation heat or cooling on one side has to be
avoided. Or appropriate precautions have to be taken.
4.2 Humidity and Dust
The torque converter corresponds to IP40 according to DIN 40050
Advice: Don’t let humidity seep into the transducer’s connector!
4.3 Chemically Resistance
The torque transducers are not resistant against chemicals.
4.4 Deposition
Dust, dirt and other particles mustn’t accumulate so that they can get into the ball
bearings and the connector.
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5. Mounting
5.1 Precautions at Assembly
•Handle the transducer carefully
•Important Note:
Do not overload the transducer, not even temporarily. If possible, we suggest
connecting the transducer to a display unit before mounting, so you can watch the
torque while mounting.
•Avoid false axial and radial alignment.
•Provide good electrical ground contact to the casing.
5.2 General Mounting Instructions
Don’t mix up the transducer’s drive side and the measuring side, as this causes errors
(especially when accelerated).
When you look at the type label the measuring side is on the left.
The measuring side also can be identified by a deepening on the cover.
Bending, axial and radial forces are causing errors. Keep thermal expanding of the
construction in mind.
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6. Measuring Chain
For measuring with the transducer, a whole measuring chain is necessary.
•Torque transducer
•Measuring cable
•Supply and display unit
You need a supply and display unit to supply the transducer with power and to display the
measured torque.
7. Connection
Connection of a torque transducer
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7.1 Hints for Connection
Electric and magnetic fields cause interference with the measuring signal. This interference
is mainly caused by power cords, relays or motors installed nearby. Besides these,
interference can be caused by multiple grounding of the measurement chain on more than
one point.
Pay attention to the following:
•Use only shielded cables with low capacitance (like our measuring cables).
•Connect supply voltage correctly (no reverse polarity protection).
•Measuring cables shouldn’t be nearby high voltage or control cables.
•Magnetic radiation from transformers, motors or relays must be avoided.
•Don’t ground transducer and display unit multiple. Connect all devices of the
measurement chain to the same ground.
7.2 Connectors
The transducer is equipped with a 12 pin fitted connector.
7.3 Pinout of the Connector
The pinout of the connectors are on the following pages.
The transducer internally generates a galvanically isolated measurement signal.
The masses must not be bridged directly on the transducer, otherwise - depending on the
cable length to the supply and evaluation device - leads to measurement errors. If
necessary, however, these can be bridged directly on the supply and evaluation device.
The “control activation” is used to test the transducer. This emits its maximum signal of
e.g. + 10V (with right-hand load). The control level is 4.5V up to the supply voltage, the
reference ground point being the supply ground.
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7.4 Prolongation of Cable
Extension cables must be shielded and have low capacitance.
We recommend using the cables we offer that meet these requirements.
In the case of cable extensions, a perfect connection and good insulation must be ensured.
It must be ensured that the cable cross-section is selected to be sufficiently large to ensure
sufficient supply voltage on the transducer.
A recalibration is not required when the cable is extended.
7.5 Supply Voltage
Regard to the correct polarity. The rise time for the supply voltage of 12V ±10% (optional
15V + 5% / -10%) should be less than 1ms, otherwise the DC/DC –converter at the
electronics might not work properly.
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8. Pin Configuration
8.1 Standard-Measuring Cable AK12.4
12-pin connector
Pin
Colour
Connection
A
Green
NC
B
Red / Blue
Angle exit track B = 90 °
C
Yellow
Moment Exit small measuring range
D
White
Moment mass
E
Grey
Supply + angle / speed ground
F
Pink
Supply +12V
G
Grey / Pink
Speed / angle output track A = 0 °
H
Purple
Memory chip small measuring range
J
Black
Memory chip large measuring range
K
Red
Control input
L
Brown
Moment output large measuring range
M
Blue
NC
(Connector at the transducer, view from above)
PIN D (torque GND) and PIN E (supply and speed GND) are internally separated.
If necessary bridge at supply source (not at the transducer!).
Built-in EMC protective circuit
Between Pin E and K; between Pin E and F as well as between Pin C and D there is a high
frequency bypass capacitor connected (100nF/50V).
We recommend carrying out this EMI protection at the supply source as well.
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8.2 Robot cable AK12.5
12-pin connector
Pin
Colour
Connection
A
Black
NC
B
Red
Angle exit track B = 90 °
C
Brown
Moment Exit small measuring range
D
White
Moment mass
E
Yellow
Supply + angle / speed ground
F
Purple
Supply +12V
G
Green
Speed / angle output track A = 0 °
H
Pink
Memory chip small measuring range
J
Grey
Memory chip large measuring range
K
Grey/Pink
Control input
L
Blue/Red
Moment output large measuring range
M
Blue
NC
(Connector at the transducer, view from above)
PIN D (torque GND) and PIN E (supply and speed GND) are internally separated.
If necessary bridge at supply source (not at the transducer!).
Built-in EMC protective circuit
Between Pin E and K; between Pin E and F as well as between Pin C and D there is a high
frequency bypass capacitor connected (100nF/50V).
We recommend carrying out this EMI protection at the supply source as well.
Applied Measurements Ltd
appmeas.co.uk
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8.3 Thin cable AK12.2 for small transducer
12-pin connector
Pin
Colour
Connection
A
Black
NC
B
Red
Angle exit track B = 90 °
C
Brown
Moment Exit small measuring range
D
White
Moment mass
E
Yellow + White/Yellow
Supply + angle / speed ground
F
Purple + Brown/Green
Supply +12V
G
Green
Speed / angle output track A = 0 °
H
Pink
Memory chip small measuring range
J
Grey
Memory chip large measuring range
K
Grey/Pink
Control input
L
Blue/Red
Moment output large measuring range
M
Blue+ shield
NC
(Connector at the transducer, view from above)
PIN D (torque GND) and PIN E (supply and speed GND) are internally separated.
If necessary bridge at supply source (not at the transducer!).
Built-in EMC protective circuit
Between Pin E and K; between Pin E and F as well as between Pin C and D there is a high
frequency bypass capacitor connected (100nF/50V).
We recommend carrying out this EMI protection at the supply source as well.
Applied Measurements Ltd
appmeas.co.uk
[email protected]

13
9.Output
The transducer’s output voltage is proportional to torque and 10V for maximum torque.
With clockwise torque the output is positive; with counter clockwise torque the output
voltage is negative.
The outputs for rotation speed and angle measurement have an open collector stage, with
an internal 10 KΩ pull up resistor in series with a diode. See schematic below.
10. Recalibration
Regardless of the use, the sensor must comply with the one specified by ETH
Period (see certificate and sticker sensor).
We also carry out a complete check (e.g. wear parts).
So that the processing can take place as quickly as possible, we recommend before the
Return an appointment.
11. Disposal
The transducer can be returned to us free of charge for disposal, complete with measuring
cable. As soon as you have packed the sensor, send a message to
[email protected], we will then commission our parcel service to collect it.
Unfortunately, we cannot accept parcels sent to us without prior notice.
Applied Measurements Ltd
appmeas.co.uk
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14
12. Angle and speed measurement at high rotation speeds
(Transducers with 360 pulses per rotation)
Remarks
• Beware of the maximum speed of your transducer type, listed in the data sheet!
• When you use a transducer with 60 pulses per rotation, the maximum speed is six times
higher than listed below.
With GMV2:
Cable length: maximum speed:
2,5 m / 8 ft 10.000 min-1
5 m / 16 ft 10.000 min-1
10 m / 32 ft 6000 min-1
With external measurement unit:
Maximum speed in RPM:
Cable length
R pull up (5V ... 12V)
10 kΩ
1,2 kΩ
2,5 m / 8 ft
4000
15.000
5 m / 16 ft
2000
12.000
10 m / 32 ft
1000
10.000
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With this circuit you can measure speed of more than 15,000 RPM and with a cable of up
to 32 ft.
The signal level of the circuit on the left hand side is suitable for opto couplers, frequency
counters, oscilloscopes and for (H)CMOS logic. If you need standard TTL levels you can add
the circuit on the right hand side.
1
+
1
1
10
kΩ
1,2
kΩ
Track A
(TTL
/CMOS)
Angle A
Transducer
Pin G
½ 74HC04
Oszilloscope
/
(H)CMOS
1
+
1
1
10
kΩ
1,2
kΩ
Track B
(TTL
/CMOS)
Angle B
Transducer
Pin B
½ 74HC04
Oszilloscope
/
(H)CMOS
12V
1
2
820 Ω
820Ω
ZPD
3V3
ZPD
3V3
Pin F
Pin F
Pin E
Pin E
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13. Technical Specifications
Applied Measurements Ltd
appmeas.co.uk
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17
13.1 Mechanical Dimensions
General tolerances DIN 2768-m
Applied Measurements Ltd
appmeas.co.uk
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13.2 Mechanical Values and Load Limits
Applied Measurements Ltd
appmeas.co.uk
[email protected]