Handling Relays; Relays For Printed Circuit Boards; Selecting Pcbs - Omron G9SA Series Manual

F Handling Relays
F-1 Vibration and Shock
Relays are precision components. Regardless of whether or not they
are mounted, do not exceed the rated values for vibration and shock.
The vibration and shock values are determined individually for each
Relay, so check the individual Relay specifications in this catalog.
If a Relay is subjected to abnormal vibration or shock, its original
performance capabilities will be lost.
G Relays for Printed Circuit Boards
(PCBs)
G-1 Selecting PCBs
(1) PCB Materials
PCBs are classified into those made of epoxy and those made of
phenol. The following table lists the characteristics of these PCBs.
Select one, taking into account the application and cost. Epoxy PCBs
are recommended for mounting Relays to prevent the solder from
cracking.
Material Epoxy
Item Glass epoxy (GE) Paper epoxy (PE) Paper phenol (PP)
Electrical • High insulation
characteristics resistance.
• Insulation
resistance hardly
affected by
moisture
absorption.
Mechanical • The dimensions
characteristics are not easily
affected by
temperature or
humidity.
• Suitable for
through-hole or
multi-layer PCBs.
Relative cost High
Applications Applications that
require high
reliability.
G-2 Selecting PCBs
(2) PCB Thickness
The PCB may warp due to the size, mounting method, or ambient
operating temperature of the PCB or the weight of components
mounted to the PCB. Should warping occur, the internal mechanism
of the Relay on the PCB will be deformed and the Relay may not
provide its full capability. Determine the thickness of the PCB by
taking the material of the PCB into consideration.
In general, PCB thickness should be 0.8, 1.2, 1.6, or 2.0 mm. Taking
Relay terminal length into consideration, the optimum thickness is
1.6 mm.
Terminal length
http://www.ia.omron.com/
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
Phenol
Characteristics New PCBs are
between glass highly insulation-
epoxy and phenol resistive but easily
affected by
moisture
absorption.
Characteristics • The dimensions
between glass are easily
epoxy and phenol affected by
temperature or
humidity.
• Not suitable for
through-hole
PCBs.
Moderate Low
Characteristics Applications in
between glass comparatively good
epoxy and phenol environments with
low-density wiring.
F-2 Dropped Products
Do not use a product that has been dropped, or that has been taken
apart. Not only may its characteristics not be satisfied, but it may be
susceptible to damage or burning.
G-3 Selecting PCBs
(3) Terminal Hole and Land Diameters
Refer to the following table to select the terminal hole and land
diameters based on the Relay mounting dimensions. The land
diameter may be smaller if the land is processed with through-hole
plating.
Terminal hole diameter (mm)
Nominal value Tolerance
0.6 ±0.1
0.8
1.0
1.2
1.3
1.5
1.6
2.0
G-4 Mounting Space
A Ambient Temperature
When mounting a Relay, check this catalog for the specified amount
of mounting space for that Relay, and be sure to allow at least that
much space.
When two or more Relays are mounted, their interaction may
generate excessive heat. In addition, if multiple PCBs with Relays
are mounted to a rack, the temperature may rise excessively. When
mounting Relays, leave enough space so that heat will not build up,
and so that the Relays' ambient temperature remains within the
specified operating temperature range.
B Mutual Magnetic Interference
When two or more Relays are mounted, Relay characteristics may
be changed by interference from the magnetic fields generated by
the individual Relays. Be sure to conduct tests using the actual
devices.
G-5 Pattern Design for Noise Countermeasures
A Noise from Coils
When the coil is turned OFF, reverse power is generated to both
ends of the coil and a noise spike occurs. As a countermeasure,
connect a surge absorbing diode. The diagram below shows an
example of a circuit for reducing noise propagation.
Noise is superimposed
on the power supply line,
so a separate pattern is
connected from a
smoothing capacitor to
supply coil power.
Smoothing
capacitor
(c)Copyright OMRON Corporation 2007 All Rights Reserved.
Minimum land diameter (mm)
1.5
1.8
2.0
2.5
2.5
3.0
3.0
3.0
The pattern will
form an antenna
circuit, so make
it as short as
possible.
Power supply line
Relay drive transistor
C-11