A16-24 Datasheet, PDF (10/16 Pages) Omron Electronics LLC – Indicator with Cylindrical 20-mm × 12-dia. Body

Technical Information
Common Precautions
For the individual precautions for a Switch, refer to the precautions
in the section for that Switch.
Cautions
Do not perform wiring or touch the charged parts of terminals while
power is being supplied to the Switch. Doing so may result in electric
shock.
Electrical Characteristics
Electrical Conditions
• The switching load capacity of the Switch greatly varies between
AC and DC. Always be sure to apply the rated load. The control
capacity will drastically drop if it is a DC load. This is because a
DC load has no current zero-cross point, unlike an AC load.
Therefore, if an arc is generated, it may continue for a
comparatively long time. Furthermore, the current direction is
always the same, which results in a contact relocation
phenomena whereby the contacts easily stick to each other and
do not separate when the surfaces of the contacts are uneven.
• Some types of load have a great difference between normal
current and inrush current. Make sure that the inrush current is
within the permissible value. The greater the inrush current in the
closed circuit is, the greater the contact abrasion or shift will be.
Consequently, contact weld, contact separation failures, or
insulation failures may result. Furthermore, the Switch may be
broken or damaged.
• If the load is inductive, counter-electromotive voltage will be
generated. The higher the voltage is, the higher the generated
energy will be, which will increase the abrasion of the contacts
and contact relocation phenomena. Be sure to use the Switch
within the rated conditions.
Inrush Current
i (Inrush current)
Technical Information
Type of Load vs. Inrush Current
Solenoid
(Approximately 10 to 20 times higher)
Incandescent
lamp (Approximately 10 to 15 times
higher)
Motor
(Approximately
5 to 10 times
higher) Relay
(Approxi-
mately 4 to 5
times higher)
• All the performance ratings given are for operation under the
following conditions unless otherwise specified.
Inductive load: A minimum power factor of 0.4 (AC) and a maxi-
mum time constant of 7 ms (DC)
Lamp load:
An inrush current 10 times higher than the
steady-state current
Motor load:
An inrush current 6 times higher than the
steady-state current
Note: Inductive loads can cause problems especially in DC cir-
cuitry. Therefore, it is essential to know the time constants
(L/R) of the load.
Load Connections
Do not contact a single Switch to two power supplies that are differ-
ent in polarity or type.
Connection of Different Polarities
The power supply may short-circuit if the loads are connected in the
way shown in the “incorrect” example below.
Incorrect
Load
o (Steady-
state current)
• Approximate control capacities are given in ratings tables, but
these alone are insufficient to guarantee correct operation. For
special types of load, with unusual switching voltage or current
waveforms, test whether correct operation is possible with the
actual load before application.
• When switching for microloads (voltage or current), use a Switch
with microload specifications. The reliability of silver-plated
contacts, which are used in Switches for standard loads, will be
insufficient for microloads.
• When switching microloads or very high loads that are beyond
the switching capacity of the Switch, connect a relay suitable for
the load.
Load
Correct
Load
Load
Even in the “correct” example, note that the insulation performance
of the switch may deteriorate and the switch life may be shortened
because loads are connected to both contacts.
14