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Installation Instructions
Original Instructions
Blind and Through-shaft Optical Incremental Encoders
Catalog Numbers 844D-A
x
, 844D-R
x
Summary of Changes
This publication contains new and updated information as indicated in
the following table.
Topic
Page
Deleted “200 kHz Push-Pull (120-8192 PPR)” from Output Frequency from the
Specifications table
Deleted “Push-Pull Single Ended Driver = ±70 mA” from Specifications table
Deleted “Code 5” in Power Supply and Output from Selection tables
Deleted “Push-pull single end driver output” graphic
Specifications
Attribute
844D-A
x
, 844D-R
x
Electrical
Code Format
2 channels with zero index
Power Requirements
120 mA (no load)
Output Frequency
300 kHz all drivers (120…8192 PPR)
600 kHz (above 8192 PPR)
Resolution
Up to 16,384 pulses per revolution
Output Driver Capability
3487 Line driver = ±40 mA
4469 Line driver = ±200 mA
7272 Line driver = ±40 mA
Mechanical
Angular Acceleration
100,000 radians/sec
2
Starting Torque @ 25 °C (77 °F)
9.3 Ncm (13 in•oz)
Running Torque @ 25 °C (77 °F)
5 Ncm (7 in•oz)
Moment of Inertia
490 gcm
2
(6.9 x x 10
-3
oz-in-sec
2
)
Slew Speed
3000 rpm maximum
Shaft Loading (120…2500 PPR)
Axial 67 N (15 lbs) Radial 133 N (30 lbs)
Shaft Loading (4096…16,384 PPR)
Axial 44 N (10 lbs) Radial 67 N (15 lbs)
Permissible Shaft Radial Movement
Static ±0.5 mm (0.02 in.) Dynamic ±0.1 mm (0.004 in.)
Permissible Shaft Axial Movement
Static ±0.5 mm (0.02 in.) Dynamic ±0.5 mm (0.02 in.)
Bore Size
Supports 1/2…1-1/8 in. and 30 mm shafts
Environmental
Protection
NEMA Type 4, 13, IP66 (IEC 529) except
terminal block connection type rated IP40 (IEC 529) only
Housing material
Aluminum
Temperature
Operating: -20…+85 °C (-4…+185 °F)
Storage: -30…+85 °C (-22…+185 °F)
Humidity
90% noncondensing
Shock
50 g (1.76 oz) for 11 ms
Vibration
20 g (0.70 oz) from 5…2000 Hz
Approximate weight
0.91 kg (2 lbs)