| Handling |
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| Shock forces (e.g., drop from a height of 30cm or more) or application of
high pull or twist forces to external terminals may result in permanent damage
to relays. |
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| Cleaning |
 |
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|
For selection of cleaners to be used on transfer molded reed relays, see the
table.
* Note: ultrasonic cleaning may cause permanent damage to the relay contacts
|
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| Freon |
Freon |
 |
| Alpha |
| Alcohol |
Ethanol |
 |
| Isopropyl alcohol |
| Chloride |
Chlorosen |
   |
| Chlorosolder |
| Trichloroethylene |
| Water-based compound |
Indusco |
 |
| Hollis |
| Thinner |
Thinner |
 |
| Gasoline |
|
 |
 |
Recommended |
 |
 |
Acceptable |
 |
 |
Conditionally Acceptable |
 |
 |
Not
Recommended |
|
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| Mounting relays on printed circuit boards |
 |
 |
- Bending of Terminals:
If it is necessary to bend relay terminals after
insertion into a printed circuit board (pcb), the bending angle (between the pcb
and the terminal) should not be larger than 45 degrees. An angle larger than 45
degrees may produce a vertical force capable of causing damage to the relay
mounted on the pcb.
- Soldering:
The following flux and solvent (cleaner) are recommended for
use on reed relays:
- Flux: non-corrosive, rosin based flux
- Solvent: chemically low active alcohol
If soldering by hand, you
must keep soldering time to a minimum; only long enough to make a good solder
joint. Excessively high temperature and/or soldering time may cause damage to
the reed switch. The recommended procedure is 3 seconds maximum at 280 to 300°C.
The recommended procedure for automatic soldering is 5 seconds maximum at 250
to 260°C.
- Placement of reed relays:
Relays are often a source of noise in
electrical circuits (e.g., in circuits using semiconductor devices), and
therefore certain precautions are recommended:
- Provide as much spacing as is feasible between reed relays and
semiconductor devices.
- Place coil suppression circuit (components) as close to the relay coil as
possible.
- Avoid laying out noise sensitive (e.g., audio circuits) traces (conductors)
in close proximity to relay coil circuits.
- As a general rule of pcb design, the shortest possible traces (conductors)
should be chosen.
- Shields or shielding pcb patterns may, in some situations, be required to
separate sensitive electronic circuits from power supplies and relays
|
 |
| Contact protection |
 |
 |
- Inductive Loads:
When using relays for inductive loads such as motors,
relay coils, solenoids, etc., the contacts will be subjected to high induced
voltages during opening of the contacts (load circuit).
Such high induced
voltages (transients) may cause damage to the reed relay's contacts and
significantly reduce its life.
Therefore, protective circuits such as: RC
(snubber), varistors or clamping diodes, are recommended.
- Capacitive Loads:
When using reed relays for capacitive loads such as
capacitors, incandescent lamps or long cables (harnesses), the reed relay
contacts will be subjected to high surge (inrush) current.
Therefore,
protective circuits such as: surge suppressors or current limiting resistors,
are recommended.
 |
 |
| Magnetic interference |
 |
 |
- The presence of strong magnetic fields caused by transformers, magnets,
iron plates, etc., in close proximity to the reed relay, may cause a change of
its characteristics and result in erroneous operation.
- Placing two or more reed relays in close proximity to one another may cause
magnetic interference between them, resulting in a change of operational
characteristics and a possible erroneous operation. To eliminate such
interference between adjacent relays, they should be spaced a minimum of 15mm
from one another.
- Note: Even when a reed relay equipped with a magnetic shield is selected (as
means of reducing magnetic interference), it is still recommended that the 15mm
minimum distance is used between adjacent relays
|
 |
| Capacitive interference |
 |
 |
| Stray
capacitances, such as between reed switch contacts and between the contacts and
the relay's coil, may cause signal coupling and cross-talk, especially at high
frequencies and with low level signals. By selecting a reed relay equipped with
electrostatic shield, such stray capacitances and the resulting signal coupling
and cross-talk are greatly reduced. |
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| Driving relays with semiconductor devices |
 |
 |
| If
a reed relay's coil is driven directly by a semiconductor device (e.g., IC,
transistor, etc.), there is a possibility of damage to the semiconductor device
caused by voltage transients induced on the relay's coil. In such cases the use
of a reed relay equipped with an internal coil suppression diode is recommended. |
|