Wiring rules and precautions specific to the TELEFAST
(Original Document)
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Connecting or disconnecting the TELEFAST
You should always connect or disconnect the TELEFAST’s connectors and various connection wires when the voltage is SWITCHED OFF:
Length of the connection cable between the module and the TELEFAST
The table below gives the clock frequency of the transmission series according to the distance.
If
then
cable length < to 10 meters
frequency of the transmission series clock: 1 MHz
cable length < to 20 meters
frequency of the transmission series clock: 750 kHz
cable length < to 50 meters
frequency of the transmission series clock: 500 kHz
cable length < to 100 meters
frequency of the transmission series clock: 375 kHz
cable length < to 150 meters
frequency of the transmission series clock: 200 kHz
cable length < to 200 meters
frequency of the transmission series clock: 150 kHz
Cross-section of the wire connecting the module and the TELEFAST
In order to reduce the on-line voltage falls as much as possible, please respect the following points:
If
And
Then
The encoder is using a 5 VDC supply
The distance from the module to the TELEFAST is < 100m
Use a wire with minimum cross-section 0.08 mm (gage 28)
The distance from the module to the TELEFAST is > 100m
Use a wire with minimum cross-section 0.34 mm (gage 22)
Connecting the encoder supply
In order to limit voltage falls with a 0V, caused by the encoder supply current, we recommend that you wire the 0V as follows:
Wiring the encoder outputs on the TELEFAST
If the encoder outputs have positive or negative logic with a number lower than 24, use the following connection procedure:
If
And
Then
the encoder outputs have positive logic
their number is lower than 24
  • wire the encoder outputs to the TELEFAST inputs, working from the least significant to the most significant
  • wire the unused TELEFAST inputs to the 0V terminal
the encoder outputs have negative Logic
their number is lower than 24
  • wire the encoder outputs to the TELEFAST inputs, working from the least significant to the most significant
  • do not wire (leave free) the unused TELEFAST inputs.
Protecting the encoder supply
According to the encoder supply voltage, the supply should be protected as follows:
If
Then
The encoder supply voltage is 10…30 VDC
The protective fuse is built into the TELEFAST:
  • size: 1A
  • type: fast-blow fusion.
The encoder supply voltage is 5 VDC
Provide a series fuse (Fu) for the positive supply:
  • calibre: to be determined by the user, dependent upon the TELEFAST and encoder consumption
  • type: fast-blow fusion
Monitoring the encoder supply
If the encoder supply voltage decreases by more than 15%, the default (EPSR signal) is sent back to the module. If the encoder does not have a return supply, do the following:
If
Then
No return encoder supply
Connect the positive and negative EPSR of the TELEFAST:
  • the positive EPSR terminal of the TELEFAST to the positive terminal of the encoder supply
  • the negative EPSR terminal of the TELEFAST to the negative terminal of the encoder supply