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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. 10
8
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. 10
7
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)