SERIES
412K
422K
HIGH-SHOCK,
HIGH-PERFORMANCE
TO-5 RELAY
DPDT
SERIES
DESIGNATION
RELAY TYPE
412K
422K
DPDT high-shock relay
DPDT high-shock magnetic-latching relay
INTERNAL CONSTRUCTION
DESCRIPTION
UPPER
STATIONARY
CONTACT
UNI-FRAME
The TO-5 relay, originally conceived and developed by Teledyne, has become one of the
industry standards for low-level switching from dry circuit to 1 ampere. Designed for high-
density PC board mounting, its small size and low coil power dissipation make the TO-5
relay one of the most versatile subminiature relays available.
LOWER
STATIONARY
CONTACT
ARMATURE
The K Series high-shock TO-5 relays are designed to withstand shock levels up to 4000
g’s, .5 millisecond duration. Special material selection and construction details provide
assurance that critical elements of the relay structure and mechanism will not be
permanently displaced or damaged as a result of extremely high g level shocks.
MOVING
CONTACT
Typical applications:
• Commercial avionics aircraft control
• Commercial aircraft control systems
• Transportation systems (rail/truck)
412K ENVIRONMENTAL AND
PHYSICAL SPECIFICATIONS
By virtue of their inherently low intercontact capacitance and contact circuit losses, the
K Series relays have proven to be excellent subminiature RF switches for applications
with frequency ranges well into the UHF spectrum. A typical RF application for the TO-5
relay is in handheld radio transceivers, wherein the combined features of good RF
performance, small size, low coil power dissipation and high reliability make it a
preferred method of T-R switching (see Figure 1 and 2).
Temperature (Ambient)
Vibration (General Note 1)
–65°C to +125°C
30 g’s to 3000 Hz
(General
Note 1)
75 g’s, 6 msec, half-sine
4000 g’s, 0.5 msec. axial
plane, half-sine
Shock
(General
Note 4)
1000 g’s, 0.5 msec side
planes, half-sine
PERMANENT MAGNET
MAGNETIC CIRCUIT B
MAGNETIC CIRCUIT A
SOFT IRON FRAME
PRINCIPLE OF OPERATION 422K
Energizing Coil produces a magnetic field
Acceleration
Enclosure
Weight
50 g’s
B
Hermetically sealed
0.09 oz. (2.55g) max.
COIL A
COIL B
opposing the holding flux of the permanent magnet
in Circuit B. As this net holding force decreases, the
attractive force in the air gap of circuit A, which also
results from the flux of the permanent magnet,
becomes great enough to break the armature free of
Core B, and snap it into a closed position against
Core A. The armature then remains in this position
upon removal of power from Coil B, but will snap
SOFT IRON
CORE A
SOFT IRON
CORE B
AIR GAP
SOFT IRON
ARMATURE
STATIONARY
CONTACT
422K ENVIRONMENTAL AND
PHYSICAL SPECIFICATIONS
Temperature (Ambient)
–65°C to +125°C
30 g’s to 3000 Hz
MOVING
CONTACT
Vibration (General Note 1)
back to position B upon energizing Coil A. Since operation depends upon cancellation
of a magnetic field, it is necessary to apply the correct polarity to the relay coils as
indicated on the relay schematic.
(General
Note 1)
100 g’s, 6 msec, half-sine
2100 g’s, 0.5 msec. axial
plane, half-sine
Shock
(General
When latching relays are installed in equipment, the latch and reset coils should not be
pulsed simultaneously. Coils should not be pulsed with less than rated coil voltage and
the pulse width should be a minimum of three times the specified operate time of the
relay. If these conditions are not followed it is possible for the relay to be in the
magnetically neutral position.
Note 4)
750 g’s, 0.5 msec side
planes, half-sine
Acceleration
Enclosure
Weight
50 g’s
Hermetically sealed
0.10 oz. (2.84g) max.
©2003 TELEDYNE RELAYS
SPECIFICATIONS ARE SUBJECT TO CHANGE WITHOUT NOTICE
www.teledynerelays.com
412K/422K Page 74
412K/422K/1203/Q1