Cameron CLIF MOCK CD-20SFA, Руководство пользователя

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CD-20SFA Sample Probe Controller
• When set by a start pulse, the RUN/STOP latch U5A outputs the speed command voltage to the summing
point control amplifier U2A.
• Amplifier U2B provides current feedback to the summing point control amplifier U2A.
• Resistor R19 provides armature voltage feedback to the summing point control amplifier U2A.
• DS2 is the current limit LED indicator.
• DS1 is the PROX (“Hold”) LED indicator.
• U2C is the proximity switch amplifier. The voltage across the proximity switch (2TB-3 to 2TB-4 on the
power board) will be nom8VDC when the proximity switch is sensing metal and +4VDC when
the proximity switch is sensing an absence of metal.
• Latch U5B outputs a single 20-msec one-shot pulse to reset the RUN/STOP latch U5A when the proxim -
ity switch first senses a high point on the cam.
Power Board Functions
The power board provides the following functions:
• Fuse F1 (2-amp, fast-acting) provides short circuit protection. ZD1, a 33V “crowbar” zener diode, pro
-
vides over voltage protection for the rest of the circuit.
• Diode D2 prevents current flow if +VDC power is connected to the common terminal and a ground is
connected to the +VDC terminal.
• Q4, an LT1074CT switching regulator and associated circuitry efficiently convert the +VDC into a regu -
lated +6.3VDC motor supply voltage.
• The control card uses motor armature feedback to set the speed command to the motor driver power FET
Q2.
• A stop command from the control card to Q1 provides motor braking which prevents the motor from
coasting past the stopping point.
• R6 is the motor current feedback resistor. The motor current is limited to 3.0 amps.
• Fuse F2 (2-amp, slow blow) will open in less than 1 minute if the motor is stalled (locked rotor).
Table 3.1—Troubleshooting Tips
Problem Probable Cause Recommended Action
Input power fuse F1 open. Input power surge above 33VDC. Check fuse F1.
Short circuit on the power board. Return to factory for
replacement of power board.
Motor Fuse F2 open. Motor stall (locked rotor). Check fuse F2.
Short circuit in motor armature circuit. Return to factory for
replacement of control card.