micro-trak MT-3405F II, Справочное руководство

Страница: 14 / 62

14
If you have a positive displacement pump or a cen trif u gal
pump capable of generating excessive pressure, you must
in stall a pressure relief valve and adjust it to a safe max i mum
pressure. If a positive dis place ment pump is operated without
a pressure relief valve, damage may re sult to pump or other
plumbing component. See Illustration 6.
Range Adjust Valve
With oversized pumps, it may be necessary to install a range
adjust valve. The range adjust valve will reduce the pump’s
output to the rest of the system.
Ad just ment of this valve is
covered in the Pre-Field System Checkout, page 32. See
Illustration 7.
Servo, Throttling Valves
For
BYPASS
installations, the servo valve installs in an
unrestricted return line to the inlet of the pump or directly
into the tank. The console must be calibrated for bypass
operation,
see Calibration section
.
DO NOT
install the servo
valve closer than 12” to the flowmeter. The servo valve has
a flow direction decal on it. Make certain that the actual
flow direction matches the decal on the servo valve. Do not
install the servo valve in the agitation line. Slow response
time and marginal operation may result. The return line
should tee from the main line just after the throttling valve.
See Illustration 8.
The throttling valve is used to limit the
output (set maximum output) of the pump to the flowmeter
and servo valve. The throttling valve is adjusted to put the
servo valve in its optimal operating range.
Please refer to
Pre-Field System Checkout on pages 32 for proper valve
adjustment procedure.
The servo valve connects directly to the 3-pin connector on
the main harness. If more length is required, use a 3-pin W/P
extension cable of the appropriate length.
IMPORTANT NOTE: If using the MT-3405F™ II with an old
style Micro-Trak servo valve, the valve voltage must be
set to 8 volts. See Special Calibration Valve Voltage section
on page 22.
NOTE: The servo valve may be installed in the main spray
line as shown in Illustration 9. For in-line installations, you
will need to calibrate the system for INLINE operation,
see page 33.
Installation (cont.)
Manual Pressure Relief Valve
Illustration 7
Tee “C”
Range
Adjust Valve
Tee “A”
For oversized pumps
Servo
Flowmeter
From Pump
Illustration 9
INLINE
For positive
displacement pumps
Illustration 6
Tee “C”
Tee “A”
Pressure
Relief Valve
Return to pump
inlet or unrestricted
return to tank
Servo Valve Cable
From Pump
Throttling Valve
To Flowmeter
Servo Valve
BYPASS
Illustration 8