Counter/Timer
How to connect a reed contact to PCI 6601 ???
Hello, I´ve got a problem trying to connect a reed contact to my counter card NI PCI 6601:
I want to make single period measurement, measuring the time between two impulses triggered by a switch (reed contact).
By consulting both manuals of NI 6601/6602 and NI 6608/6609 I found out that the impulse line has to be connected to gate input, and the timebase to source input.
Problem is how do I connect the wires? - I guess I´ve got to use a pull-down resistor:
A resistor placed between a digital input and ground is called a "pull-down" resistor because it normally pulls the pin's voltage down to ground. A switch placed between the digital input and the voltage supply will short the digital input to the voltage supply when it is pressed. This means the voltage seen at the input will be low when the switch is open and high when the switch is closed.
My questions:
-Can I use the 5V supplied by the NI 6601 card? Is it allowed to connect this or other 5V source directly (by pressing the switch) to the gate input?
-How do I know the value of the pull-down resistor? Is it the standard value of 4,7 kOhms? The Ni 6608 has this resistor onboard- does the NI 6601 also have it already implemented or do I have to attach it externaly?
-Maximum current at the input isn´t allowed to exceed 0,2mAmperes - Is this secured by the card´s circuit?
-Should I preferably use a pull-up resistor? Between 5V supply and input (gate)?
Thanks in advance for answering my questions !!!
I want to make single period measurement, measuring the time between two impulses triggered by a switch (reed contact).
By consulting both manuals of NI 6601/6602 and NI 6608/6609 I found out that the impulse line has to be connected to gate input, and the timebase to source input.
Problem is how do I connect the wires? - I guess I´ve got to use a pull-down resistor:
A resistor placed between a digital input and ground is called a "pull-down" resistor because it normally pulls the pin's voltage down to ground. A switch placed between the digital input and the voltage supply will short the digital input to the voltage supply when it is pressed. This means the voltage seen at the input will be low when the switch is open and high when the switch is closed.
My questions:
-Can I use the 5V supplied by the NI 6601 card? Is it allowed to connect this or other 5V source directly (by pressing the switch) to the gate input?
-How do I know the value of the pull-down resistor? Is it the standard value of 4,7 kOhms? The Ni 6608 has this resistor onboard- does the NI 6601 also have it already implemented or do I have to attach it externaly?
-Maximum current at the input isn´t allowed to exceed 0,2mAmperes - Is this secured by the card´s circuit?
-Should I preferably use a pull-up resistor? Between 5V supply and input (gate)?
Thanks in advance for answering my questions !!!
