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RDAG12-8 Manual
ISOV+ and ISOGND:
This is the power connection for the isolator section that may be supplied
from the computer's +12VDC supply via a pair of wires on the RS-485
network or from a central power supply. This power is independent of
"local power". The voltage level can be from 7.5 VDC to 35 VDC. (An
on-board voltage regulator regulates the power to +5 VDC.) RDAG12-8
will require only about 5 mA of current when idling and ~33mA current
when data is being transmitted so any loading effects on the computer
power (if used) will be low.
Note
If separate power is not available, ISOV+ and ISOGND must be jumpered to the "local power"
terminals, which defeats the optical isolation.
RS485+ and RS485-:
These are the terminals for RS485 communications (TRx+ and TRx-).
APPLV+:
This terminal is a single common pin for the cathodes of the inductive
suppression diodes included in the 7 Digital Outputs. If a Digital Output is
controlling a Relay coil a suppression diode (aka flyback diode) is required
to limit the voltage spike at the output pin when the Relay coil is turned off.
If different Relay coil voltages are controlled at the Digital outputs then
only the highest voltage can be connected to the APPLV+ pin.
APG0-7:
These terminals are for use with the High Power version of the Pod
(RDAG12-8H). Connect all load returns to these terminals.
AOGND:
These terminals are for use with the Low Power version of the Pod. Use
these for returns of voltage outputs as well as current outputs.
GND:
These are general purpose grounds which can be used for Digital Bit
returns, Power return connections, and so on.
To ensure that there is minimum susceptibility to EMI and minimum radiation, it is important that
there be a positive chassis ground. Also, proper EMI cabling techniques (cable connected to chassis
ground, twisted pair wiring, and, in extreme cases, ferrite-level of EMI protection) may be needed
for input/output wiring.
VOUT0-7:
Analog Output Voltage signal, use in conjunction with AOGND
IOUT0-7:
4-20mA Current Sink Output signal, use in conjunction with an external
power supply (5.5V to 30V).
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Manual MRDAG12-8H.Bc2