Max Machinery 286-300 SERIES TRANSMITTERS - Manual (Page 2)

General Description
The 286-3XX Series Transmitter converts the rotary motion of the metering elements inside a Max Flow
Meter into a frequency proportional to the flow rate. This is accomplished using a differential transformer
technique, which puts no torque requirements on the flow measuring elements and enables extremely fast
output response rates. A microprocessor measures position changes of the metering elements and generates
the corresponding output pulse stream.
When used with the Max Series 210 Piston Flow Meters, these transmitters will compensate for cyclical
variations in rotational velocity of the metering pistons (inherent in the four piston design) to give a steady
output frequency.
The 286-3XX Series circuitry has self-calibration routines that can be initiated with the push of a button.
This simplifies matching of flow meter and transmitter in the event that field maintenance is required.
The Model 286 features an antidither output buffer. If the flow reverses (for less than ½ revolution of
the flow meter), and then returns to the forward direction, the transmitter pulse output will represent only
the total forward flow. The two-phase output is not buffered; it is an instantaneous indicator of metering
element position. The antidithering is a useful feature when the flow stops or is very low, and vibration or
hydraulic noise causes the flow metering elements to reverse direction.
The transmitter can be powered from a 4.5V to 30VDC supply. The user can select between two types
of outputs: a square wave output or a two-phase output where the frequency of each phase is half that of the
square wave output. The user can select from square wave outputs of 24, 50, 100, 200, 300, 500, 600 or
1000 pulses per revolution, or two-phase outputs of 12, 25, 50, 100, 150, 250, 300 or 500 pulses per
revolution (on each phase).
General Description
286-300-350 © 2002, Max Machinery, Inc. (2)
Discontinued