A42M Incremental Rotary Encoder
A42M Rotary Encoder Drawing

Ø42mm incremental encoder

A42M

Optical modular rotary encoder A42M is of incremental type and provides up to 25.000 output pulses per revolution. The absence of bearings and lubricants makes the encoder suitable for use in vacuum environment or situations when zero starting torque is required.

Mechanical data

Number of output pulses per revolution 1000-25000
Line number on disc (z) 1000; 2500 (others on request)
Max. permissible mechanical rotation speed 20000 rpm
Accuracy (T1-period lines on disc in arc. sec) ± 0.1T1 arc. sec
Permissible axial shaft runout 0.05 mm
Hub inside diameter 10, 8, 6 mm
Rotor moment of inertia < 22 gcm²
Protection (IEC 529) IP00
Maximum weight rotor assembly: 0.022 kg
scanning unit: 0.04 kg
Operating temperature -10…+70°C
Storage temperature -30…+85°C
Maximum humidity (non-condensing) 98%
Permissible vibration (55 to 2000 Hz) ≤ 100 m/s²
Permissible shock (6 ms) ≤ 1000 m/s²

Electrical data

Version A42M-A ∫ µApp A42M-AV ∫ 1 Vpp A42M-F Π TTL; Π HTL
Supply voltage + 5 V ± 5 % + 5 V ± 5 % + 5 V ± 5 %; + (10 to 30) V
Max. supply current (without load) 80mA 120 mA 120 mA
Light source LED LED LED
Incremental signals Two sinusoidal I1 and I2
Amplitude at 1 kΩ load:
– I1 = 7 – 16 µA
– I2 = 7 – 16 µA		 Differential sine +A / -A and +B / -B
Amplitude at 120 kΩ load:
– A = 0.6 – 1.2 V
– B = 0.6 – 1.2 V		 Differential square-wave U1 / U1 and U2 / U2. Signal levels at 20 mA load current:
– low (logic “0”) ≤ 0.5 V at Up =± 5V
– low (logic “0”) ≤ 1.5 V at Up = 10 to 30 V
– high (logic “1”) ≥ 2.4 V at Up =±5V
– high (logic “1”) ≥ (Up – 2)V at Up = 10 to 30 V
Reference signal One quasi-triangular I0 peek per revolution. Signal magnitude at 1 kW load:
– I0 = 2 – 8 µA (usable component)		 One quasi-triangular +R and its complementary -R per revolution. Signals magnitude at 120 W load:
– R = 0.2 – 0.8 V (usable component		 One differential square-wave U0 / U0 per revolution. Signal levels at 20 mA load current:
– low (logic “0”) < 0.5 V at Up =± 5V
– low (logic “0”) < 1.5 V at Up = 10 to 30 V
– high (logic “1”) > 2.4 V at Up =±5V
– high (logic “1”) > (Up – 2)V at Up = 10 to 30 V
Maximum operating frequency (-3 dB) ≥ 160 kHz (-3 dB) ≥ 160 kHz (160 x k) kHz, k – interpolation factor
Direction of signals I2 lags I1 for clockwise rotation (viewed from shaft side) + B lags + A in clockwise rotation (viewed from shaft side) U2 lags with U1 in clockwise rotation (viewed from shaft side)
Maximum rise and fall time – – < 0.5 μs
Maximum cable length 5 m 25 m 25 m

Accessories

Downloads

Product Catalog
Encoder Selection Guide 2025
A42M Rotary Encoder Datasheet
A42M Incremental Rotary Encoder 2D Drawing
A42M Incremental Rotary Encoder 3D Drawing

Order code

A42M – X1 – X2/X3 – X4 – X5/X6

Output Signal Version (X1) Pulse Number per Revolution (X2) Hub Inside Diameter (X3) Adapter Cable (X4) Connector Type for Adapter Cable (X5)
AV
F		 1000
…
2500*
*only F signal version for >2500 pulses		 06 – ⌀6mm
08 – ⌀8mm
10 – ⌀10 mm		 W – without cable
AC01 – 1m
AC02 – 2m
AC03 – 3m
…		 W – without connector
B12 – round, 12 pins
C12 – round, 12 pins
D9 – flat, 9 pins
D15 – flat, 15 pins
RS10 – round, 10 pins
ONC – round, 10 pins

ORDER EXAMPLES: 

  1. A42M-AV-2500-10-AC01/W
  2. A42M-F-5000-06-W-W

Order form

    Check the "Order code" tab in the product page to see how to know your order code.