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IMPORTANT: It is important to point out that unlike the AC type pump-switching
units, the DC type units require a power supply of 12v DC without which they would
not function. When the pump-switching unit is commanded by the local I/O of the
DREAM or the remote I/O expansion unit, the 12v can be taken from the power
supply of the DREAM or of the expansion unit. However when the DC pump-
switching unit is activated through an RTU (either 2W or RF), the 12v powering
cannot be taken from the RTU resources but must be externally supplied. If solar
powering is required by a 2.5W solar panel and a rechargeable battery of 3Ah.
9.2 The three functions of the REBRAN board
The following paragraph describes a special board that can be used in three different ways
depending on the setting of the jumpers onboard. We call it the REBRAN board, the name is
derived from the three functions the board can fulfil:
RE = stands for REPEATER; BR = stands for BRIDGE; AN = ANALOG INPUTS INTERFACE
9.2.1 RS485 Repeater with optic isolation
When serving as a REPEATER the REBRAN board is meant to sit on the RS485
communication line and isolate one side of the line from the other. The input side and the
output side of the board are connected onboard through opto-couplers that make the two sides
JP7,9,10,11
define the
powering
side
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