TeeJet TASC-6600 - Manual (Page 44)

6-2
TASC-6000, 6300, 6600 98-05010
Rev. - 1
6.2. FLOW CONTROL VALVE FAILURE
The TASC can still be operated in the event of a flow control valve failure. To operate the sprayer, it is necessary to
manually adjust the flow control valve so that sufficient pressure is available to the booms to give a good spray pattern.
Thus, there is no longer positive control over the main carrier flow, but; the chemical injection control system continues
to operate in a normal, fully controlled manner. Use the following procedure to manually position the flow control valve.
Application rate accuracy is reduced when operating under these conditions.
A. Stop the sprayer, turn all booms OFF and put the console into Manual Override (see section 3.8).
C. Disconnect the flow control valve at the cable connector.
D. Use a nozzle chart to determine the boom pressure that gives the desired application rate of carrier at the target
speed. Turn ON the normal boom sections and allow the carrier to spray. Manually rotate the stem of the flow
control valve (It may be necessary to remove the electric actuator to adjust the valve. Be sure to mark the
valve position before removing the power head.) and/or adjust the pump bypass valve to generate the desired
pressure downstream of the main carrier pump. Turn all boom sections OFF.
CAUTION: NEVER USE A SPARGE LINE WHILE OPERATING THE INJECTION PUMPS.
E. Turn ON the desired chemical injection pumps, to the rate desired, start the vehicle and proceed to the applica-
tion area, accelerating to normal spraying speed. As the vehicle reaches the start of the desired swath, turn on
the booms and begin spraying. At this point, the operator is enjoying all the control and monitoring functions of
TASC, with the exception of positive control of the flow control valve.
F. All volumes and areas will accumulate normally. The chemical injection pumping rates respond normally to
changes in boom configuration, ground speed or pump application rate changes commanded by the operator.
Carrier flow rate can be monitored by turning the Display Selector to "Carrier Application Rate". The flow rate
reads out in gallons per minute, when the actual ground speed is less than one MPH, and in gallons per acre
when ground speed is above one MPH. Thus, although this is at best a temporary solution to the valve failure,
the application accuracy of the injected chemicals is still maintained.
G. To exit the Manual Override Mode reenter some Carrier Application Rate, other than zero, into the console.
6.3. FLOWMETER FAILURE
The TASC 6300 or 6600 can still be used to control chemical injection rates, even if the system experiences a failure of
the flow meter. The procedure is very similar to operating without the flow control valve, except, in this instance, the
flow control valve is cycled using a manual override procedure. Application rate accuracy is reduced when operating
under these conditions.
A. Stop the sprayer, turn all booms and injection pumps OFF and put the console into Manual Override (see
section 3.8). Disconnect the flowmeter wiring harness at the first connector back from the flowmeter (3 pin
connector).
B. The Flow Control Valve now responds only to manually activated commands from the INC/DEC switch on the
Control Console. The TASC console remains in this configuration until some Carrier Application Rate other
than zero is entered into the Control Console
C. Use a nozzle chart to determine the boom pressure that gives the desired application rate of carrier at the target
speed. Turn ON the desired boom sections and allow the carrier to spray. Adjust the boom pressure using the
INC/DEC switch on the Control Console. INC opens the Flow Control Valve and DEC closes the valve. The
rate of movement of the valve increases the longer the switch is held. Once the desired pressure is attained, turn
all boom sections OFF.
CAUTION: NEVER USE A SPARGE LINE WHILE OPERATING INJECTION PUMPS.