Xylem H-335 - Manual (Page 11)

H-335
H-335 Operation 1-7
SillAngle = ArcSin
TrunnionElevation -SillElevation
GateRadius
ArcSin
391'-363'
36'
= 51057 .
board. This eliminates stressing the connector and circuit board while tightening the terminal block screws.
Make certain the wires do not touch any of the internal components, especially if your cable has a bare
drain wire.
1.8 Programming the H-335
The H-335 has several fixed constants which must be programmed before installation. We recommend
doing this in the lab, before installing the H-335 on the tainter gate.
Step 1: Program the sensor with the proper SDI-12 address, make certain each sensor has a unique
sensor address. See Chapter 2 for details of the “aAn” change address command.
The H-335 comes from the factory with the following settings:
Sensor Address: 0
UserAngleSlope: +1.0
UserAngleOffset: 0.0
GateRadius: 36.0
SillAngle: 51.057
With these values the GateHeight and GateArcLength parameters will be in units of feet for a gate with a
radius of 36.0 feet. The setup is stored in EEPROM within the H-335 and will not be lost if the power is
disconnected. The extended commands for changing these settings is described in detail in Chapter 2.
Use the extended SDI-12 commands “aXWCn” and “AaXRCn” to write and read respectively the
following settings:
Step 2 (coefficient 1): Set the UserAngleSlope as needed for your installation. Set the slope to +1.0
for a gate which opens clockwise while facing the H-335 cover. Set the slope to
-1.0 for a gate which opens counter-clockwise while facing the sensor cover
(see Figure 2).
Step2 (coefficient 2): Make certain the UserAngleOffset value is set to 0.0.
Step3 (coefficient 3): Set the GateRadius as needed for your tainter gate. This is the distance between
the center of the trunnion bearing and the outside face of the skin plate. This value also determines the units
for the GateArcLength and GateHeight data output values. If this value is in units of feet, the data output
will be in units of feet etc.
Step4 (coefficient 4): Set the SillAngle as needed for your tainter gate. Use a calculator and the
following formula to compute the proper value:
For Example: