Ametek Drexelbrook 505-1320 Series, Инструкция по установке и эксплуатации

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10
505-1320 Series Ultrasonic Open Channel Flowmeter
TM
SECTION 3
OPERATION
3.1 Modes of Operation
3.2 Indicators & Controls
When using the 505-1302 Open Channel Flowmeter, there
are two modes of operation: flow or distance mode.
•••••
In the flow (or level) mode, the current output (4-20 mA)
increases as the liquid level rises.
•••••
In the distance mode, the current output increases as the
level falls (distance to the transducer increases).
•••••
The desired span range may be set from a minimum of 3.0
inches up to 87.9 inches (99.9 inches minus 12-inch near
zone).
Refer to Figures 3-1 and 3-2 for the location of indicators and
controls.
—SW8 Flow or Distance Mode
Normal operation, and the selection of either flow or distance
mode is accomplished by changing the position of switch 4 on
SW8. See
Section 3.1 Modes of Operation .
—Time Delay Control
The time delay control is located above SW8. A zero-second
time delay (position 2) is the default selection that is set at the
factory. Position 4 sets a 15-second time delay. Position 1 sets
a 45-second time delay.
—Zero and Span Calibration Switches
The zero and span are each set using three, ten-position
rotary switches. Zero and span settings are made in inches
with 0.1-inch resolution. Zero and span switches are used to
calibrate the unit. See
Section 4.2 Standard Calibration .
—LED Indicators
Two LED indicators are located on the transmitter to alert the
user to a near zone or lost echo fault condition or improper
calibration.
—Calibration Pushbutton
The calibration pushbutton is used in conjunction with SW8
for maximum calibration accuracy. See
Section 4.4 Secondary
Calibration . This button can also be used as a system reset.
—Flow Switches
Three, ten-position rotary switches are used to set the type
and size of the flume or weir. The top switch sets the type and
the two lower switches set the flume or weir size in degrees or
inches. See
Section 4.2 Primary Device Selection .