London Electronics INTUITIVE INT2 Series, Детали подключения, масштабирование и общая информация

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The serial output board plugs onto the 0, 2 or 4 alarm upper option board.
It plugs onto a pair of connectors and is secured by a snap-pillar.
The 120 Ohm termination resistor should be fitted to only the last display on an RS485 data link,
to improve noise immunity. A terminator should also be fitted on the sending device.
The bias jumpers are not normally fitted, but are available if your system needs biasing, to keep
it in a valid idle state when data is not present.
Re-assemble the meter, apply power and follow the Serial Output Settings procedure on the
next page.
Handy Feature
You can tell if a serial output is fitted to your meter by viewing the ‘Summary’ display. Press the
two outer buttons of the display for 3 seconds. You will also see the summary when you first
switch on your meter.
AL1 AL2 AL3 AL4
Serial Data
Comms Option
Analogue
Output
Option
RS232 board
No jumpers needed
RS485 board
If fitted, connects 120 Ohm terminator
If fitted, sets a bias of +0V on Sig A
If fitted, sets a bias of +5V on Sig B
Typical UART output
RS485 data line levels
S 0 0 1 1 0 1 0 0 S
B(-)
A(+)
S 0 0 1 1 0 1 0 0 S
A(+)
B(-)
Warning:
Disconnect all cables from
option board before adjusting
Serial Output - page 1
Where the product is intended for “UL” installations
removal or addition of option boards is not permitted.
!
Warning:
Disconnect
all power before exposing
the rear of the meter