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« on: October 04, 2014, 02:46:42 PM »
Hi Dave:
The pin1, Enable signal does not specifically connect to the Pokeys board. It is activated by a "High", +5v, or a "Low", 0v. The Enable signal tells the amp to turn on, or off.
In most systems, the amps cannot turn on until Mach3 is in control. This is is accomplished by the "Charge Pump" output signal, which is a 5kz signal that can cause a "Safety Charge pump" to activate a relay, which turns on the "Enable" circuit of the amplifier.
CNC4PC sells a little board which measures about 2" square, which can read this 5kz output signal. it has a relay with a N/O, Com, N/C terminals, and a red LED which turns on when the 5kz signal is output by Mach3. The Pokeys board will output the Charge Pump signal. The Pokeys specs will tell you how to connect to the correct pin for the Charge Pump output signal.
In the case of the PoStep 25-32, the Enable pin must see 0 volts, logic "0"; this is backwards from most other amps, which need a +5v signal, logic "1" The earlier
PoStep 25 amp was +5v "Enable," 0v "Disable." I am sure the Engineers at Pokeys had reasons to change the polarity, however it makes it difficult to mix the older Amp with the newer model.
When the Enable signal is working properly, the Amp will light up a green led, showing it is Active. If you use a CNC4PC charge pump, wire the Enable pins of the amps to the NC terminal of the relay, and a +5v to the Com. When the system is first turned on, the +5v goes direct to the Enable pins, and the Amps will be in the "Disable" state. When Mach3 is in control, the 5kz signal will pull in the relay, and the +5v will be directed to the N/O pin, which has nothing connected to it, and the N/C pin will go "Low", or 0v, and the Amps will turn on, "Enable."
This Enable/Disable is necessary because you don't want the amps to turn on until Mach3 is running, and the system is in control.
The 2,4,6,8,10 pins can be all tied together, and a single wire from that goes to GND.
John