micro-trak MT-2400 LR, Справочное руководство

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If you have a positive displacement pump or a cen trif u gal
pump capable of more than 65 PSI (4.5 bar), you should
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 13.
Servo, Throttling Valves
The servo valve installs in an unrestricted return line to
the inlet of the pump or directly into the tank. It is not
recommended to 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 15. 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. Using your manual controller’s electric valve for the
throttling valve may simplify the adjustments. Please refer
to Pre-Field System Checkout for proper valve adjustment
procedure.
Illustration 15
Illustration 14
Illustration 13
Installation
(cont)
Pressure Relief Valve
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. Adjustment of this valve is
covered in the Pre-Field checkout, page 36. See Illustration 14.
Tee “C”
Tee “A”
Pressure
Relief Valve
For positive displacement pumps
Tee “C”
Range
Adjust Valve
Tee “A”
For oversized pumps
Return to pump
inlet or unrestricted
return to tank
Servo Valve Cable
From Pump
Throttling Valve
To Flowmeter
Servo Valve
The servo valve connects directly to the main harness 3-pin
W/P cable lead. If more length is required, use a 3-pin W/P
extension cable of the appropriate length. If using a Braglia
or other 12­volt control valve, please refer to 12­Volt Control
Valve Calibration on page 48.
NOTE: Although not recommended, the servo valve can
be installed in the main spray line. For in-line installations,
you will need to cut the servo cable and reverse the wires.
Connect the RED wire to the BLACK wire and vise versa.
Failure to reverse the wires will result in the servo valve
operating backwards.