The S850 snap-action switch can open two galvanically isolated safety circuits with one actuation. Equipped with one positive opening for both break contacts, the S850 represents a favourable solution for control system engineers who want to increase the safety level of machines and systems without investing in additional hardware, installation or programming. This high-quality microswitch is suitable for safety-related applications as outlined in DIN EN ISO 13849-1.
Double break contact with two galvanically isolated contact bridges. Both contact pairs are opened when the snap-action switch is actuated.
A contact bridge spreads the breaking capacity over two contact points. The contact material is silver. For the switching of high direct currents, we recommend blow magnets for preventing electric arcs (optional).
If the break contacts fuse in the event of a short circuit, the catch spring can no longer open. It is nevertheless opened reliably via the lever of the positive opening. This is a positive opening as outlined in DIN EN 60947-5-1, annex K.
In every switching process, the contact bridges rub in a defined fashion on the V-shaped fixed contacts and remove corrosion and combustion residue. Permanently low contact resistances ensure a high level of contact reliability throughout the service life.
With self-cleaning silver contacts, small currents can be connected reliably and frequently. In chemically aggressive environments and with low switching frequencies, we recommend gold contacts.
This is the maximum dimensions of the housing. The dimensions of the actuator and of the connections must be added. For all dimensions and drawings please refer to the following product catalogue:
Contact configuration | Double NC contact switch with 4 terminals, positive opening operation, wiping action, and 2 galvanically isolated contact bridges |
10 A at T = 85°C | |
5 A at T = 85°C | |
400 V | |
300 V | |
Pollution degree IEC 60947 | PD 3 |
Pollution degree UL508 | PD 3 |
4 kV | |
Utilization category IEC 60947 | AC-15, 230 VAC/1.5 A / DC-13, 24 VDC/1.5 A |
Utilization category UL508 | 240 V AC General Purpose / 4 A |
IP40/IP20 | |
Contact material | Silver or gold-plated silver |
Short-circuit protection | 10 A gG |
Actuator | Phush button, roller lever |
Free position | 8.85 ±0.15 (push button) |
Operating position | 6.60 ±0.25 (push button) |
Release position | 7.80 ±0.25 (push button) |
Total positive opening travel | 5.80 (push button) |
Total travel position | < 5.65 (push button) |
Movement differential (between operating and release position) | 1.20 (typical, push button) |
Front mount | yes, front mounting by nut retainers M3 |
Ganging (side mount) | yes, side mount |
Vibration resistance | 15 g (10 … 500 Hz all directions (without aux. actuator at 0.1 ms max. opening time) |
Shock resistance | 30 g, half sinus (without aux. actuator at 0.1 ms max. opening time) |
Housing material | PC, green, transparent |
Mechanical endurance | 1.5 million cycles min. |
Temperature range | -55°C ... +85°C |
Note | Data valid for new switches with silver contacts |