2014.02
industrial.panasonic.com/ac/e/
Panasonic Corporation 2014
©
–1–
ASCTB45E 201402-T
RELAY SOLDERING AND CLEANING GUIDELINES
As electronic devices become more
compact, it is becoming a common
practice to weld the relay to a PC board
(along with the semiconductors) rather
than using plug-in relays with sockets.
When relays are welded, their
functionality may be affected due to
seepage of flux into the relay. Therefore,
the following precautions are provided for
soldering a relay onto a PC board.
Please refer to them during installation in
order to avoid problems.
The protective measures used will
determine suitability for automatic
soldering or automatic cleaning. Please
follow the recommendations listed in
“Configuration and Construction” section.
1.
MOUNTING OF RELAY
• Avoid bending the terminals to make the
relay self-clinching. Relay performance
cannot be guaranteed if the terminals are
bent. Self-clinching terminal types are
available depending on the type of relay.
• Correctly drill the PC board according to
the given PC board pattern illustration.
• Stick packaging is also available for
automatic mounting, depending on the
type of relay. (Be sure that the relays
don’t rattle.) Interference may occur
internally if the gripping force of the tab of
the surface mounting machine is too
great. This could impair relay
performance.
Bad example
2. FLUX APPLICATION
• Adjust the position of the PC board so
that flux does not overflow onto the top of
it. This must be observed especially for
dust-cover type relays.
• Use rosin-based non-corrosive flux.
• If the PC board is pressed down into a
flux-soaked sponge as shown on the
right, the flux can easily penetrate a dust-
cover type relay. Never use this method.
Note that if the PC board is pressed down
hard enough, flux may even penetrate a
flux-resistant type relay.
Bad example
3. PREHEATING
• Be sure to preheat before using
automatic soldering. For dust-cover type
relays and flux-resistant type relays,
preheating acts to prevent the
penetration of flux into the relay when
soldering. Solderability also improves.
• Preheat according to the following
conditions.
• Note that long exposure to high
temperatures (e.g. due to a
malfunctioning unit) may affect relay
characteristics.
Temperature
120
°
C
248
°
F
or less
Time
Within approx. 2 minutes
