RI-21AAA - COTO Technology

100 COTO TECHNOLOGY (USA) Tel: (401) 943-2686 / Fax (401) 942-0920 6 (Europe) Tel: +31-45-5439343 / Fax +31-45-5427216

RI-21 Series Dry Reed Switch

RI-21 Series

Micro dry-reed switch hermetically sealed in a gas-filled envelope.

Single-pole, single-throw (SPST) type, having normally open contacts,

and containing two magnetically actuated reeds.

The switch is of the double-ended type and may be actuated by an

electromagnet, a permanent magnet or a combination of both.

The device is intended for use in sensors, relays, pulse counters or

similar devices.

RI-21 Series Features

 General purpose reed switch

 High breakdown voltage

 Contact layers: Gold, plated ruthenium

 Superior glass-to-metal seal and blade alignment

 Excellent life expectancy and reliability

General data for all models RI-21

AT-Customization / Preformed Leads

Besides the standard models, customized products can

also be supplied offering the following options:

! Operate and release ranges to customer

specification

! Cropped and/or preformed leads

Coils

All characteristics are measured using the Philips

Standard Coil. For definitions of the Philips Standard

Coil, refer to “Application Notes” in the Reed Switch

Technical & Application Information Section of this

catalog.

Life expectancy and reliability

The life expectancy data given below are valid for a

coil energized at 1.25 times the published maximum

operate value for each type in the RI-21 series.

No load conditions (operating frequency: 100Hz)

Life expectancy : min. 108 operations with a failure

rate of less than 10-9 with a confidence level of 90%.

End of life criteria:

Contact resistance > 1Ω after 2 ms

Release time > 2 ms (latching or contact sticking).

Loaded conditions (resistive load: 12 V; 4 mA;

(15 mA peak); operating frequency: 170 Hz)

Life expectancy: min. 107 operations with a failure rate

of less than 10-8 with a confidence level of 90%.

End of life criteria:

Contact resistance > 2Ω after 4 ms

Release time > 0.7 ms (latching or contact

sticking). Switching different loads involves

different life expectancy and reliability data. Further

information is available on request.

Mechanical Data

Contact arrangement is normally open; lead finish is

tinned; net mass is approximately 190 mg; and can be

mounted in any position.

Dimensions in inches (mm)

101

For Most Recent Data, Consult the Coto Technology Website: www.cotorelay.com 6 E-mail: info@cotorelay.com

RI-21 Series Dry Reed Switch

Shock

The switches are tested in accordance with “IEC 68-2-

27”, test Ea (peak acceleration 150 G, half sinewave;

duration 11 ms). Such a shock will not cause an open

switch (no magnetic field present) to close, nor a switch

kept closed by an 80 AT coil to open.

Vibration

The switches are tested in accordance with “IEC 68-2-

6”, test Fc (acceleration 10G; below cross-over fre-

quency 57 to 62 Hz; amplitude 0.75 mm;

frequency range 10 to 2000 Hz, duration 90 minutes).

Such a vibration will not cause an open switch (no

magnetic field present) to close, nor a switch kept

closed by an 80 AT coil to open.

Mechanical Strength

The robustness of the terminations is tested in accor-

dance with “IEC 68-2-21”, test Ua1 (load 40 N).

Operating and Storage Temperature

Operating ambient temperature; min: -55°C;

max: +125°C. Storage temperature; min: -55°C; max:

+125°C. Note: Temperature excursions up to 150°C

may be permissible. For more information contact your

nearest Coto Technology sales office.

Soldering

The switch can withstand soldering heat in accordance

with “IEC 68-2-20”, test Tb, method 1B: solder bath at

350 ±10°C for 3.5 ±0.5 s. Solderability is tested in

accordance with “IEC 68-2-20”, test Ta, method 3:

solder globule temperature 235°C; ageing 1b: 4 hours

steam.

Welding

The leads can be welded.

Mounting

The leads should not be bent closer than 1 mm to the

glass-to-metal seals. Stress on the seals should be

avoided. Care must be taken to prevent stray magnetic

fields from influencing the operating and measuring

conditions.

Model Number

RI-21AAA RI-21AA RI-21A RI-21B RI-21C

Parameters Test Conditions Units

Operating Characteristics

Operate Range AT 8-16 14-23 18-32 28-52 46-70

Release Range AT 4-14 7.5-17.5 8-22 12-29 16-32

Operate Time - including bounce (typ.) energization 100 AT ms 0.1 (20AT) 0.25 (29AT) 0.25 (40AT) 0.25 (65AT) 0.25 (88AT)

Bounce Time (typ.) energization 100 AT ms 0.05 (20AT) 0.15 (29AT) 0.15 (40AT) 0.15 (65AT) 0.15 (88AT)

Release Time (max) energization 100 AT

s70 (20AT) 30 (29AT) 30 (40AT) 30 (65AT) 30 (88AT)

Resonant Frequency (typ.) Hz 5500 5500 5500 5500 5500

Electrical Characteristics

Switched Power (max) W 10 10 10 10 10

Switched Voltage DC (max) V 200 200 200 200 200

Switched Voltage AC, RMS value (max) V 250 250 250 250 250

Switched Current DC (max) mA 500 500 500 500 500

Switched Current AC, RMS value (max) mA 500 500 500 500 500

Carry Current DC; AC, RMS value (max) A 1 1.5 2.5 2.5 2.75

Breakdown Voltage (min) V 225 325 375 500 650

Contact Resistance (initial max) (energization) m

Ω

100 (20 AT) 100 (25 AT) 100 (30AT) 100 (40 AT) 100 (40 AT)

Contact Resistance (initial typ.) (energization) m

Ω

70 (20 AT) 70 (25 AT) 70 (30 AT) 70 (40 AT) 70 (40 AT)

Contact Capacitance (max) without test coil pF 0.3 0.3 0.25 0.25 0.25

Insulation Resistance (min) RH

≤

45% M

Ω