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the Normally Closed circuit is opened) it causes a fault condition, which shuts down the steppers, turns on the red fault LED, and brings pin 15 (the Fault signal) high, telling Mach 3 a fault condition exists. It is one of the reasons you should enable the use of the "charge pump." You don't want your router to turn on just because the system is booting!ħ. This is good, since PC parallel ports are notorious for coming up with the pins in an undetermined state. It also means that when the power is applied to the computer and the G540, the outputs from the G540 are dead until Mach 3 is running and providing the 12.5 kHz "charge pump" signal. This means that if the unit is or goes into a fault, the outputs are turned off. All the outputs are gated with the fault condition. This especially useful for troubleshooting if you are only using 3 of the axes anyway.Ħ. However, you can remove all of the G250s and plug them in one at a time (with the power off, of course, and then once plugged in apply power) to see which one may have the fault. If there is something wrong with any of the G250s, the fault light on the G540 will not go out. It appears to be soldered, but on very close inspection it is actually socketed.ĥ. This fuse looks like an unstriped 1/2 watt resistor (actually it is a 0.04 ohm 2 watt resistor) and located just under and to the right of connector pos 12. If the polarity of the power supply is reversed, or if you switch the DC side of the power supply, instead of the AC side, it will blow a very fast acting fuse in the unit.
#Gecko g540 fault light Pc
On the newer models you can just flip the switch to remove the need for a "charge pump" signal, and you don't need the PC hooked up at all to get out of fault condition.Ĥ. The later rev labels the switch "on" (required) or "off" (not required.) The documentation kind of says the only thing you need to do to get out of fault mode is to apply power and ground, and ground out pin 10 (i.e., connect a normally closed Estop switch to it.) However, you must also have the parallel cable plugged into the PC and Mach3 running and configured for a charge pump to get the fault condition to go out. The switch has 2 positions - "charge pump required" or "charge pump not required" - the units normally ship with the switch in the "charge pump required" position, which is with the slider moved towards the center of the board. Of course this means the computer has to spend beaucoup instruction cycles just to keep it charged up, but it does provide some protection that the computer hasn't lost its thread. This name probably reflects the idea that the computer's constant pulse keeps a capacitor/semiconductor charged up to a particular voltage, and the 540 faults if it ever drops below that. This "charge pump" is an odd name for a watchdog timer - i.e., so that the G540 can tell if the computer is still running as it should, it needs an occasional (12,500 times a second!) nudge from the computer to tell it that Mach 3 is still running, and hasn't gone off to lala land. On earlier models, the switch is buried inside the unit, right next to connector pos 12. On models made after May, 2009 the switch is external on the lower right hand side of the front cover. There is a switch on the G540 to turn off or on the requirement to have a "charge pump" present.
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Actually, these LEDs are part of the voltage regulator for each drive as well.ģ. Also, inside the box, each of the 4 G250 drives have a separate red LED that is on when power is applied. Kind of like a stop n go light - red means stop, while green means go. If you have power applied correctly, one but not both of the LEDs should be lit. The "power" LED on the front of the unit is kind of misnamed - it is more of a "ready" light that is only on if and when the fault light is off. Despiking capacitors on inputs to ground are not necessary.Ģ. The inputs, including the estop switch (pos 10 on the connector) are already despiked for noise and debounced for switch issues. This is some otherwise undocumented information about the G540 (and the four G250 drives buried inside) that I've learned since I've been using it:ġ.
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The Gecko G540 is a great device in that it crams an amazing amount of functionality into a very small space.
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