SMAR DFI302, Руководство пользователя

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DFI302 – Installing
2.5
Using the Fault Indication
The 1B and 2B Terminals available in the DF51, may be used in a Fault Indication application.
Actually, these terminals are only an NC Relay.
The NC Relay supports:
0.50 A @ 125 Vac
0.25 A @ 250 Vac
2.00 A @ 30 Vdc
* valid data for resistive loads.
Normally, DF51 forces this relay to stay open, but if any bad condition crashes the CPU, the
hardware will close it. This status may be used in redundancy situation where the backup processor
reads this contact and knows about the fault. Another choice is to use it to goes off an alarm.
Jumpers on Board
The W1 jumper (from DF51) must be enabling to make possible simulations through the Simulate
(SIMULATE_D or SIMULATE_P) parameters of output and input function blocks.
Do not use W2 and W3 jumpers. They are only used to download firmware in the factory.
Improving Signal Ground in the DFI302
Besides the fact that the Racks of the DFI302 system are connected by flat-cables for signal and
power transportation, we may face on some fading in the Signal Ground for applications that make
use of many Modules. A solution to keep the Signal Ground stable and the system more immune to
electrical noises is to add an extra wire between Racks.
These wires should follow the flat cable path to avoid ground loops. Wire must be strained and have
a diameter of at least the AWG18.
For adjacent Racks, use the “extending connector” that comes with the Rack on its left side.
Obviously, it is possible to have a system with adjacent and non-adjacent racks.
NOTE
Always use the Terminator Board in the last rack.