Electronics 500-24 - Manual (Page 3)

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1. PRODUCT DESCRIPTION
The 500-24xx Series of MagnaValves are designed to regulate the flow of steel shot or grit in
abrasive blast cleaning and shot peening machines. The valves have a magnetic control sec-
tion (upper portion) and a shot flow rate sensing section (lower portion). Valves are sized by
flow rate capacity, either in pounds/minute or in Kg/minute, and are used in air-blast applica-
tions such as direct pressure, suction blast or gravity-fed nozzle blast machines.
Specify calibration in pounds/minute or Kg/minute and type and size of shot with order.
2. THEORY OF OPERATION
MagnaValves have no moving parts, they rely upon very strong permanent magnets and can-
cellation electromagnets to regulate the flow rate of shot. A signal from a shot flow controller,
model FC-24, will provide the appropriate control signal for flow rate. Power is supplied by an
external (supplied by customer) 24Vdc source. The internal circuitry accepts a 0-10Vdc control
signal and converts this to a proportional duty-cycle control of the output signal for shot flow. As
the shot falls through the lower sensing portion of the valve, a 0-10Vdc signal is generated and
sent back to the FC-24 controller as a flow feedback signal. This feedback signal is compared
to the requested shot flow rate and the output signal is adjusted and sent back to the Magna-
Valve to complete the closed-loop cycle of control.
3. LOCATION OF ADJUSTMENTS
All of the adjustments are accessible from the front of the MagnaValve. See figure 1 for details.
The factory settings should not be changed. The rated flow range is shown on the identification
label. The output signal is 10 Vdc. for calibrated valves.
4. PRELIMINARY ADJUSTMENTS
There are no preliminary adjustments required or recommended. The valve has been tested
and calibrated at the factory prior to shipment. The full-scale range of the valve and the media
type and size are listed on the product label.
5. INSTALLATION
The MagnaValve must be mounted in a vertical position with an adequate supply of media
above it.
6. OPERATON
Signals used to operate the MagnaValve originate at the FC-24 Controller. There are three con-
ditions necessary for correct operation. See figure 1 for additional information.
a. Power – The 24 Vdc power must be continuously applied to the valve. The valve requires
4Amps for operation and a power supply rated at 1000 VA. The voltage should be 24  2
Vdc.
b. Enable – The 24 Vdc enable signal is used to activate the valve.
Note: All MagnaValves are factory calibrated to Kg/min=10 Vdc. To
change to pounds/min see instruction manual for the FC-24 Controller.
Flow Range
MagnaValve Model Output = 4.54 Vdc Output = 5.00 Vdc
500-24 1200 Lbs/min 500 Kg/min
500-24B 1200 Lbs/min 500 Kg/min