User's Manual
14
LIAIRE02-03
Warnings for installation
AUTEC - Air series
3.4 Wiring
The power supply of the receiving unit must be connected using an omnipolar
switch with a switch-contact gap of at least 3 mm, that allows power supply
disconnection during installation, wiring and/or maintenance operations.
The receiving unit's power supply must be protected against short circuit
by means of an external device (e.g. fuse, thermal magnetic circuit breaker).
Such device must be able to interrupt the maximum fault current (including
the short circuit current) allowed in the circuit.
Receiving units powered with AC and exposed to transient overvoltages
exceeding those of overvoltage category II, require additional protections
that must be provided outside of the receiving units themselves.
If the receiving unit is powered with direct current, the power supply must
come:
- from a power supply unit with a safety isolating transformer, or
- from a 12/24V battery.
Relay outputs of receiving unit's commands are dimensioned so as to
control power loads. Contacts of those outputs are protected by means of
over-voltage suppressors (varistors), to ensure the maximum lifetime of
relays in most applications.
Suppressors connected in parallel with contacts of commands' relays may
be incompatible with the connection to a high-impedance load (e.g. some
PLCs); please contact Autec to perform correct installation.
Loads connected to the relay outputs must ensure the minimum power,
voltage and current value that the contacts can switch with good reliability
(300mW, 5V, 5mA). Connect an additional load to the outputs if necessary.
If a receiving unit's output (be it a solid state output or the contact of a relay)
controls a DC inductive load (i.e. solenoid valves, relays), it is advisable to
connect a recovery diode in anti-parallel with the driven load, to reduce the
eectsofdemagnetizingcurrents.