
Reed Switches
Overview of Reed Switches

Oki reed switches have extremely high-quality due to our proprietary technologies -- contact surface deactivation treatment, high-performance automatic sealing machines, and contact resistance measurement based on the flux scanning (FS) system. These technologies have earned us the top market share in the World. Also, our broad product line allows the customer to select a product to suit the intended application and purpose, for everything from low-voltage signal lines to high-voltage power lines.
Reed Switch Structure and Principle of Operation

The reed switches comprise two ferromagnetic reeds placed with a gap in between and hermetically sealed in a glass tube. The glass tube is filled with inert gas to prevent the activation of the contacts. The surfaces of the reed contacts are plated with rhodium or iridium.

The reed switch is operated by the magnetic field of an energized coil or a permanent magnet which induces north (N) and south (S) poles on the reeds. The reed contacts are closed by this magnetic attractive force. When the magnetic field is removed, the reed elasticity causes the contacts to open the circuit.

The transfer type reed switch is normally ON, due to mechanical bias of the common (COM) lead, which is between the normally closed (N.C) reed contact and the normally open (N.O) reed contacts.

When an external magnetic field is induced, the N.C blade is not affected because it is non-magnetic but the COM lead is attracted by the N.O lead and moves. When the magnetic field is removed, COM lead again moves to the N.C lead by mechanical
Reed Switch Typical Characteristics
You can download various data of our reed switches in detail, from "Document Download" page.
| Part no. | Contract type | Contact capacity | Outer dimensions (mm) | Features (Contact material) | ||
|---|---|---|---|---|---|---|
| Glass tube length | Glass tube diameter | Total length | ||||
| ORD213 | 1A | 1W | 7.0max | Ø1.80max | 35.8 ± 0.3 | Super ultra-miniature (Rh) |
| ORD213S-1 | 1A | 1W | 7.0max | Ø1.80max | 13.0 | Super ultra-miniature SMD(Rh) |
| ORD211 | 1A | 1W | 10.0max | Ø2.0max | 35.7 ± 0.3 | Ultra-miniature (Rh) |
| ORD219 | 1A | 10W | 12.0max | Ø2.00max | 44.3 ± 0.3 | Miniature high-performance (Rh) |
| ORD221 | 1A | 10W | 13.0max | Ø2.30max | 44.2 ± 0.3 | Miniature off-set type (Rh) |
| ORD2221 | 1A | 10W | 13.0max | Ø2.30max | 56.7 ± 0.3 | Miniature off-set type long lead(Rh) |
| ORD228VL | 1A | 10W | 14.0max | Ø2.20max | 44.3 ± 0.3 | Miniature high-performance (Rh) |
| ORD228S-1 | 1A | 10W | 14.0max | Ø2.20max | 19.6 ± 0.3 | Miniature high-performance SMD (Rh) |
| ORD229 | 1A | DC50W/AC70W | 21.0max | Ø2.75max | 55.4 ± 0.3 | High breakdown voltage (Rh) |
| ORD2210 | 1A | DC50W/AC70W | 21.0max | Ø2.75max | 55.4 ± 0.3 | High power (Rh) |
| ORD2210V | 1A | 100W | 21.0max | Ø2.75max | 55.4 ± 0.3 | Vacuum, high power (Rh) |
| ORD2211 | 1A | 50W (12V 3.4W lamp) | 16.5max | Ø2.80max | 44.1 ± 0.3 | Lamp load (Rh) |
| ORD234 | 1A | 10W | 21.0max | Ø3.50max | 43.4 ± 0.3 | Long-life (Rh) |
| ORT551 | 1C | 3W | 14.0max | Ø2.54max | N.O51.6 ± 0.3 N.C56.1 ± 0.3 |
Ultra-miniature transfer (Rh) |
| ORD311 | 1A | 10W | 7.0max | Ø1.80max | 35.8 ± 0.3 | Super ultra-miniature long-life (Ir) |
| ORD312 | 1A | 30W | 12.0max | Ø2.00max | 44.3 ± 0.3 | High-power long-life (Ir) |
| ORD324 | 1A | 10W | 14.0max | Ø2.2max | 44.3 ± 0.5 | High-power long-life (Ir) |
| RA-901 | 1A | 10W | 2.5 ± 0.1(W) | 2.5 ± 0.1(H) | 19.5 ± 0.2(L) | Miniature SMD (Molded type) |
| RA-903 | 1A | 1.0W | 2.1 ± 0.1(W) | 2.1 ± 0.1(H) | 12.3 ± 0.2(L) | Ultra-miniature SMD (Molded type) |
Proximity Switches
Overview of Proximity Switches

We fabricate proximity switches with high contact reliability using high-reliability, high-quality reed switches based on our unique contact surface deactivation treatment technology. These reed switches have the top market share in the World. We use our own reed switches, so we can realize precise operating characteristics and functions.
Proximity Switch Product List
| Part no. | Contact type | Contact capacity | Package dimensions(mm) | Features (Description) | ||
|---|---|---|---|---|---|---|
| H | W | L | ||||
| RA-110 Series | 1A | 10W | 6.0 | 10.0 | 32.0 | General-purpose proximity switch |
| RA-600 Series | 1A | 10W | 19.0 | 6.0 | 29.0 | PCB mounted open type |
| RA-700 Series | 1A | 10W | 19.0 | 4.0 | 24.0 | Miniature PCB mounted open type |
Shock Sensors
Overview of Shock Sensors

Through our technical alliance with Hamlin Electronics (USA) we have commercialized an electric safety sensor used in automotive air bag systems. RRPC Series products are comprised of a reed switch, magnet and spring. During acceleration detection, the magnet moves and the reed switch actuates. This actuation is adjusted to meet specifications suited to the characteristics of each vehicle determined computer simulation, so products can be supplied with a short lead time.
Shock sensor product list
| Part no. |
Contact configu- ration |
External dimensions (mm) |
Switching voltage (V) (Reference value) |
Switching current (A) (Reference value) |
Contact resistance (mΩ) |
Shock sensitivity (Reference value) |
Features (Descrip- tion) |
|||
|---|---|---|---|---|---|---|---|---|---|---|
| H | W | L | Actua- tion time (ms) |
ON hold time (ms) |
||||||
| RRPC 1A07 Series |
1A | 20.7 | 12.2 | 12.7 | 16max | 10max | 150max | 8.0 max |
18.0 max |
Horizontal 1 contact |
| RRPC 1B07 Series |
1B | 20.7 | 12.2 | 12.7 | 20max | 16max | 150max | 8.0 max |
18.0 max |
Horizontal 1 contact |
| Remarks | Does not include terminals |
ON for 5ms each time |
HaverSine 15ms 20G |
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