Installation and operation manual
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Version RCM-10/03-e
Installation Page
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5.5 Serial port jumpers
With the two jumpers installed vertically the serial output can be used with a straight
through DB-9 serial cable and connect directly to a PC serial input port. With the
jumpers installed horizontally the serial port can be used to connect directly into a
PDA.
6. Operation
The RCM-2000 detector contains a nonconductive ceramic tube mounted in a stainless
steel housing. Two DC pulsed electromagnetic coils are mounted in the stainless housing
outside of the tube. Two platinum electrodes are inserted into the ceramic tube
perpendicular to the coils. When the coils are energized, a magnetic field is created
across the whole diameter of the tube. When a conductive fluid flows through this
magnetic field, a voltage is induced across the electrodes based upon Faraday’s law.
f
f
s
V
kDB
e
=
This voltage is directly proportional to the average flow velocity of the fluid and is picked
up by the two electrodes. This induced voltage is then amplified and processed digitally
by the converter to produce a very accurate analog or digital output signal. The signal can
then be used to indicate flow rate and totalization or to communicate to remote
controllers. The main advantages of this technology are that with no parts in the flow
stream, there is no pressure loss, the accuracy is not affected by temperature, pressure,
viscosity, density or flow profile and with no moving parts, there is practically no
maintenance required.
