ZD630/640 & ZA630/640 Dual Input Counters Operation modes-Single, Dual, Differential, & Summing-2 Encoders

Model Numbers

ZD 630-634  Dual Electronic Counter (8 decades) 
ZD 640-644  Dual Electronic Counter (6 decades) 
ZA 630-634 Dual Electronic Counter (8 decades, analogue output)
ZA 640-644 Dual Electronic Counter (6 decades, analogue output)


  • Counter series with two separate encoder inputs, each A, /A, B, /B, with individual impulse scaling (1 MHz each input channel)
  • Operating modes as Single Counter, Dual Counter (independent), Differential coutner {encoder1 - encoder2} or Summing counter {encoder1 + encoder2} of two encoder positions, and many other useful counting functions
  • Universal inputs TTL/HTL for any kind of impulse sources like single-channel (A only), quadrature (A/B) or differential (RS422 A, /A, B, /B) 
  • All models provide 4 presets with 4 fast-switchign optocoupler outputs (1 msec) and RS232 serial interface (RS485 optional)


 AC Power Supply 24 V~±10%, 15VA 
 DC Power Supply 24 - (17-40V), approx. 100mA (+encoders) 
Aux. Encoder Supply Outputs: 

2 x 5,2 VDC, 150 mA each

2 x 24 VDC, 120 mA each


2 universal encoder inputs (internal pull-down resistor, Ri = 8.5kΩ each channel)

4 digital control inputs HTL (Ri = 3.3 kΩ) Low <2.5 V, High > 10V, min. pulse width 50 usec.

 Counting frequency (per encoder)

RS422 and TTL differential: 1MHz (min. differential voltage 1V)

HTL single-ended: 200kHz

TTL single-ended: 200kHz 

 Switching Output (All models) 4 fast power transistors 5-30V, 350 mA(b) , Responcse time < 1 msec (a), 
 Relay outputs (models ZD6xx, ZA6xx and ZR6xx only) Serial Link 4 relays (dry changeover contacts) (b) AC switching capability max. 250 V/ 1 A/ 250 VA; DC switching capability max. 100 V/ 1A/ 100 W 
 Ambient Temperature

Operation: 0-56°C (32 - 113°F)

Storage: -25 - +70°C (-13 - 158°F) 

Housing  Norly UL94-V-0 
Display  6 Digit, LED, high- efficiency red, 15mm 
 Protection Class (front side only)

All models without front thumbwheels: IP65

All models with front thumbwheels: IP20

(with plexi-glass cover part #64026 also IP65) 

 Protection Class rear side  IP20 
 Screw Terminals Cross section max. 1.5mm² 
 Conformity and standards: EMC 2004/108/EC: EN61000-6-2, EN61000-6-3; LV2006/95/EC: EN61010-1 


ZD630 Dual Counters Diagram