RI-44 Series Dry Reed Switch
RI-44 Series
Micro dry-reed switch hermetically sealed in a gas-filled glass 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 where high voltages need to be switched.
RI-44 Series Features
High voltage breakdown voltage
Can handle up to 40W load
Contact layers: gold, rhodium
Superior glass-to-metal seal and blade alignment
Excellent life expectancy and reliability
Dimensions in inches (mm)
General data for all models RI-44
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
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
Life expectancy and reliability
The life expectancy data given below are valid for a coil
energized at 1.5 times the published maximum operate
value for each type in the RI-44 series.
Loaded conditions (resistive load: 20 V; 500 mA;
operating frequency: 125 Hz)
End of life criteria:
Contact resistance > 2Ω after 2.5 ms
Release time > 2.5 ms (latching or contact sticking).
Switching different loads involves different life expectancy and reliability data. Further information is
available on request.
Other loads, contact Coto for more detail.
Mechanical Data
Contact arrangement is normally open; lead finish is
tinned; net mass is approximately 280 mg; and can be
mounted in any position.
The switches are tested in accordance with “IEC 68-227”, test Ea (peak acceleration 500 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.
Operate Sensitivity > 25AT
MCBF 250M operations
COTO TECHNOLOGY (USA) Tel: (401) 943-2686 / Fax (401) 942-0920
(Europe) Tel: +31-45-5439343 / Fax +31-45-5427216
RI-44 Series Dry Reed Switch
(1)Switching Power: The product of switching voltage and switching current may not exceed the indicated switching power.
(2) Contact Coto for more details.
The switches are tested in accordance with “IEC 68-26”, test Fc (acceleration 10 G; below cross-over frequency 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.
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
The leads can be welded.
Mechanical Strength
The robustness of the terminations is tested in accordance with “IEC 68-2-21”, test Ua1 (load 40 N).
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
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.
For Most Recent Data, Consult the Coto Technology Website:
E-mail: [email protected]