Rs-422/485 Settings; Rs-485 Line Failsafe Biasing; Rs-485 Line Termination; Rs-422 Full Duplex Mode - Brainboxes ES Series Product Manual

Protocol Type – Telnet: Data is sent over the Transmission Control Protocol using a
o
virtual terminal connection.
Local TCP Port: Configures which TCP port the ES device will use.
Connection Timeout: This is set to "0" by default. If the Connection Timeout is set to
anything other than 0, the connection to the port will be disconnected automatically after
being idle (i.e. no data is being received or sent to and from the port) for the specified time.
The LED for the port will go off at this point. If the Connection Timeout setting is "0", the port
will need to be disconnected manually by the user.

RS-422/485 Settings

The factory default RS-422/485 setting is full duplex mode.
The RS-485 standard talks about the differential pair as 'Data A' and 'Data B' but line driver chip
manufacturers use the labels 'Data+' and 'Data-'.
'Data A' is the inverting pin 'Data-' and 'Data B' is the non-inverting pin 'Data+'
If you can't get the connection to work it may be because you have mistakenly connected the lines the
wrong way round.

RS-485 Line Failsafe Biasing

Since RS-485 devices have to take turns to send data on the bus there are times when the bus lines
are idle, (not driven by any device) and they float to an indeterminate state generating false data.
To solve this; at each end of the RS-485 bus, add a pull up and a pull down resistor to put the line into
a known, good state during idle times. Brainboxes products have factory fitted bias resistors that are
jumper enabled.

RS-485 Line Termination

Reflections at the end of the twisted pair cable run can interfere with data on the line and so can
cause errors.
Brainboxes products have factory fitted termination resistors that are jumper enabled. Fit the jumper
ONLY if this device is at the end of the cable

RS-422 Full Duplex Mode

This mode is generally used between one transmitter / receiver to only one other transmitter /
receiver, but it is possible for each output to drive up to 10 receivers.
In RS-422 mode, the ES industrial range of devices have 4 pins, TxD+, TxD-, RxD+ and RxD-. Thus 2
twisted pair cables are used. One twisted pair carries the TxD data outwards, one pair brings the RxD
data inward.
This mode is generally used between one transmitter / receiver to only one other transmitter /
receiver, but it is possible for each output to drive up to 10 receivers.
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ES Industrial Range
Product Manual V3.3
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© Copyright Brainboxes Ltd
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