EC2/EE2 SERIES
16
1. Notes on contact load
Make sure that the contact load is within the specifi ed range;
otherwise, the lifetime of the contacts will be shortened
considerably.
Note that the running performance shown is an example, and
that it varies depending on parameters such as the type of
load, switching frequency, driver circuit, and ambient
temperature under the actual operating conditions.
Evaluate the performance by using the actual circuit before
using the relay.
2. Driving relays
- If the internal connection diagram of a relay shows + and -
symbols on the coil, apply the rated voltage to the relay in the
specified direction. If a rippled DC current source is used,
abnormalities such as beat at the coil may occur.
- The maximum voltage that can be applied to the coil of the
relay varies depending on the ambient temperature.
Generally, the higher the voltage applied to the coil, the shorter
the operating time. Note, however, that a high voltage also
increases the bounce of the contacts and the contact opening
and closing frequency, which may shorten the lifetime of the
contacts.
- If the driving voltage waveform of the relay coil rises and falls
gradually, the inherent performance of the relay may not be
fully realized. Make sure that the voltage waveform
instantaneously rises and falls as a pulse.
- For a latching relay, apply a voltage to the coil according to
the polarity specifi ed in the internal connection diagram of the
relay.
- If a current is applied to the coil over a long period of time,
the coil temperature rises, promoting generation of organic gas
inside the relay, which may result in faulty contacts. In this
case, use of a latching relay is recommended.
- The operating time and release time indicate the time
required for each contact to close after the voltage has been
applied to or removed from the coil. However, because the
relay has a mechanical structure, a bounce state exists at the
end of the operating and release times. Furthermore, because
additional time is required until the contact stabilizes after
being in a high-resistance state, care must be taken when
using the relay at high speeds.
3. Operating environment
- Make sure that the relay mounted in the application set is
used within the specifi ed temperature range. Use of a relay at
a temperature outside this range may adversely affect
insulation or contact performance.
- If the relay is used for a long period of time in highly humid
(RH 85% or higher) environment, moisture may be absorbed
into the relay. This moisture may react with the NOx and SOx
generated by glow discharges that occur when the contacts
are opened or closed, producing nitric or sulfuric acid. If this
happens, the acid produced may corrode the metallic parts of
the relay, causing operational malfunction.
- If any material containing silicon (silicon rubber, silicon oil,
and silicon based coating material) is used in the neighborhood
of relay, there is some possibility that these materials will emit
silicon gas that will penetrate the relay. In this case, the
switching contact may generate silicon compounds on the
surface of contacts. This silicon compound may result in
contact failure. Avoid use of relay in such an environment.
- Because the operating temperature range varies depending
on the humidity, use the relay in the temperature range
illustrated in the figure below. Prevent the relay from being
frozen and avoid the generation of condensation.
- The relay maintains constant sealability under normal
atmospheric pressure (810 to 1,200 hpa). Its sealability may be
degraded or the relay may be deformed and malfunction if it is
used under barometric conditions exceeding the specified
range.
- The same applies when the relay is stored or transported.
Keep the upper-limit value of the temperature to which the
relay is exposed after it is removed from the carton box to
within 50℃.
- Permanent magnets are used in polarized relays. For this
reason, when magnets, transformers, or speakers are located
nearby the relay characteristics may change and faulty
operations may result.
- If excessive vibration or shock is applied to the relay, it may
malfunction and the contacts remain closed. Vibration or shock
applied to the relay during operation may cause considerable
damage to or wearing of the contacts. Note that operation of a
snap switch mounted close to the relay or shock due to the
operation of magnetic solenoid may also cause malfunctioning.
NOTE ON CORRECT USE