ESAB YardFeed 200, Руководство по обслуживанию

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S0740 800 148/E060619/P30
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The first version of the control board, 0486 991 880
:
If the current relay does not operate within one second after starting, the motor
speed increases to the set speed in any case.
YardFeed 200
The creep start function is always activated.
13AP1:5 Motor driving / braking
Driving
The motor is powered from the sm60 V supply. Motor speed is
controlled by pulse width modulation of transistor Q1. The pulse frequency is
39 kHz, the old version of the board has a pulse frequency of 12 kHz. The
maximum conducting time of the pulses is 99% of the pulse cycle time. During
the pulse spaces, the motor current freewheels through diode D8.
At 24 V motor supply voltage, the wire feed rollers’ speed is 160 r/min. A wire
feed speed of 20 m/min. requires a roller speed of 217 r/min.
Current limit
Resistor R19 produces a voltage drop proportional to the motor current. If the
current exceeds the current limit, IC5 turns off the gate pulses to Q1. When the
current falls, Q1 conducts again at the next gate pulse.
The new version of the control board (0487 162 880) has a dynamic current
limit controlled by the processor. The current limit is 11 A on starting. When the
set speed is achieved, this is reduced to 7 A.
The first version of the control board (0486 991 880) has a fixed current limit at
7 A.
Braking
When the motor starts, capacitor C43 charges up via diode D28: the voltage is
limited to 15 V by zener diodes D10 and D21. When the motor is to brake, the
LED in optocoupler IC8 lights, causing the transistor in IC8 to conduct and