Type 634/635 is an electromechanical mini-totalizing counter with a 6 or 7-digit optical display, with standard pattern connector arrangement. The small dimensions and low power consumption make this the ideal device for front panel installation or PCB use. Types 1 and 3 can be machine-soldered and can, if necessary, be washed with no problems. The 634 variant is characterised by its excellent protection against magnetic disturbance, while model 635 is particularly impact-resistant.
| Product Family | 634/635 | 
| Function | Totalizing counter | 
| Technology | Electromechanical | 
| Digits | 6-digit | 
| Display | 			
  | 		
| Preset | none | 
| Digit Height [mm] | 4 mm (0.2 in), visual | 
| Voltage | 			
  | 		
| Reset | without reset | 
| Duty Cycle at 25 °C | 100 % | 
| RI + RV [Ohm] | 320-3720 | 
| Power Consumption | 60 400 mW | 
| Pulse Length min. | 50 ms | 
| Supply Voltage | 			
  | 		
| Count Frequency [Hz] | 10 Hz | 
| Count Input | adding | 
| Electrical Connection | 			
  | 		
| Maintenance-Free operation | 10? pulses | 
| IP Protection Class | IP65, IP66 | 
| Operating Temperature [°C] |  10 + 50 °C (+ 14 ... 122 °F) | 
| Storage Temperature [°C] |  40 + 85 °C (+ 14 ... 122 °F) | 
| Degree of Protection | 			
  | 		
| Susceptibility to Magnetic Interference | type 634 with 100 kA/m (328 kA/ft) (PTB) no effect | 
| General Design | EN 61 010-1 / IEC 61010-1 | 
| Vibration Resistance | 			
  | 		
| Shock Resistance | 			
  | 		
| Protection Class | II, EN 61010-1 / IEC 61010-1 | 
| Contamination Level | 			
  | 		
| Size [mm] | 			
  | 		
| Mounting Options | Various variants | 
| Mounting | 			
  | 		
| Reset | without reset | 
| Weight [g] | approx. 10 g (3.2 oz) | 
| Mounting Position | horizontal rolling axis |