7
3.5 ELECTRICAL CONTROLS
The electric Hurricane RC monitor is controlled by a very powerful, state-of-the-art electronics system. The key components of the
system are the motor control boards and a communication board. Each motor control board has it's own microprocessor and a
sophisticated motor control chip. The communication board also has a microprocessor, which handles the interface to the operator
stations. All the components on these boards are solid state; there are no relays or electro-mechanical devices to wear out over time.
The hardware and software have been designed with several key features.
3.5.1 MOTOR CONTROL BOARD (MCB) AUTO CONFIGURE
Each monitor has three MCBs, one for each motor, which controls motor movement and direction for horizontal rotation, elevation, and
nozzle pattern. In the unlikely event of a MCB failure, the failed board can be removed and one of the other two remaining MCBs can be
moved into that position. This MCB will then auto configure itself to take over the control of that axis, so that the monitor can continue to
be used, with two of the three motors. This is also a helpful benefit when troubleshooting and requires fewer spare parts to be stocked.
3.5.2 MOTOR CURRENT LIMITING
The microprocessor on the MCB continuously monitors the motor current. As the motor reaches an end stop or if there is an
obstruction, the motor current rises very quickly and the motor control chip automatically shuts down the motor in a few milliseconds.
This eliminates the need for any type of external limit switches and the associated wiring. The microprocessor also locks the operator
from moving in the stopped direction again, until the operator first moves in the opposite direction.
3.5.3 MOTOR SOFT STOPS
The horizontal and vertical motors are equipped with feedback encoders, which allow the microprocessor to know the motor position
at all times. The first time a motor reaches an end stop or strikes an obstruction, the microprocessor sets a new soft stop position just
before the end stop. From that point on when the axis approaches the stop, the MCB automatically slows down the motor until the end
stop is reached. This significantly reduces the wear on the motor, gearbox, and external gears.
3.5.4 MOTOR SLOW/FAST SPEED
When an operator presses one of the buttons, the associated motor starts in slow speed mode so that the operator can accurately
control the water stream. After approximately 1-2 seconds the motor automatically ramps up to a fast speed, for quickly moving into
position.
3.5.5 COMMUNICATION PROTOCOL
The communication from the monitor to the operator stations is performed over two wires using RS-485 serial protocol. Multiple
operator stations can be added with only two wires for power and two wires for the RS-485 protocol between each station.
4.1STRUCTURAL REQUIREMENTS
FOR MONITOR MOUNTING
The structure that the Hurricane RC Monitor is mounted to must
withstand the internal pressure of the monitor as well as shear and
bending forces due to nozzle reaction. Nozzle reaction can be as
high as 1,050 lbs (480 kg) (1250 gpm at 200 psi).
For flanged connections the use of flat flanges without raised faces
is recommended. Use a full-face gasket as defined in SME 16.21 or
ISO 7483. Tighten flange bolts in an alternating sequence as
shown in figure 4.1. Tighten to 76-80 ft-lb (100-110 Newton-
Meters).
4.0 INSTALLATION
Injury can result from an inadequately supported monitor. The monitor mount must be capable of
supporting the nozzle reaction force which can be as high as 1500 lbs (700 kg). Flanges and pipe
made from plastic are inadequate for monitor mounting and must not be used. This monitor is not
recommended for portable use.
WARNING
FIG 4.1A -
Flange Bolt Tightening Sequence
Tighten sequentially each bolt three times.
1
1
2
2
3
3
4
4
1
1
2
2
3
3
5
5
6
6
7
7
8
8
4
4
3.5.6 OSCILLATE AND STOW FEATURES
The OSCILLATE feature allows the user to program up to 65 points of continuous movement of the horizontal and vertical axes. The
OSCILLATE pattern can be programmed from any operator station that has the OSC button.
The STOW feature allows the user to move the monitor, with one touch of a button, to a safe position before moving the fire truck. The
monitor will always move to two end stops to verify the correct position. During the programming procedure the user has the ability to
select which axis moves first. This is helpful to avoid lights, hoses, obstructions, etc. The user can program up to 10 points of
movement to reach the final STOW position. The STOW pattern can be programmed from any operator station that has the STOW
button.
