Hi. My name is Matt, and I'm a support engineer at Agilent Technologies. And today we’re
going to talk about how to wire two Agilent power supplies up for remote inhibit operations,
so when a fault on one occurs, the other one shuts down and vice versa.
So what I have here is an N6705A DC power analyzer. And underneath it, I have an N6700B
module power supply mainframe. So the first thing we’re going to look at is the wiring
required to use this function. So let’s take a look at that.
So what we have here is a simple pictorial representation of the two 8-pin digital connectors
that you’ll be using to connect the fault inhibit operation. These connectors were included
with the mainframe when they shipped. And if you want more information about how to
do this, look at the appendix in the manual entitled “Using the Digital Connector.”
So we’re just going to use some different colored markers to show the different wires
you need to connect. So the first wire you’re interested in is Pin 1, what I have labeled
Connector 1, which I’ll be putting into my N6705A. It’s Pin 1, which is the fault
signal. So it’s the fault output.
So what you want to do is connect the fault output on Connector 1 to the inhibit input
on Connector 2, which is going into the N6700B. You then want to connect the fault common
on Float Connector 1 to the inhibit common, which is Connector 2’s Pin 8.
And in a similar vein, you’re going to want to connect Pin 1, which is fault on Connector
2 to Pin 3 on Connector 1, which is the inhibit input. And then Pin 2 on Connector 2,
which is the common for the fault, to Pin 8 of Connector 1.
And after you have that all done, you can plug the digital connector into the rear panel
of the two mainframes, and then you turn the units on. So now we’re just going to take
a look at the settings you have to do on the front panel.
This is the front panel display of the N6705A. We’re going to start by pressing the Menu key,
and then scroll down to the Utilities menu item and hit the Enter button,
and scroll down to the Digital I/O.
So the two pins we’re concerned about right now are Pins 1 and 3. So we’re going to
take Pin 1, which is set to Digital I/O right now and set that to Fault Out. Then we go
to Pin 3, which is also set to Digital I/O. But we’re going to set that to Inhibit In,
and then close our menu here, and then go back to the meter – any meter you want.
So what we can also do here is press the Settings button, scroll down to the Protections,
go to Advanced. And there’s an option here to make inhibit Live or Latched. And as you
can see here, I already turned it off. We’re going to leave it on Live.
But the difference between live and latched is that when it’s live, when the inhibit
signal goes away, the unit will automatically come back to its previous state. If it’s
in CV, it’ll go back to CV. If it’s in CC, it’ll go back to CC. Otherwise, in latch,
it’ll stay protected until you go to the unit and clear a protection.
So now we’re going to take a look at the front panel of the N6700B and make
pretty much the same settings.
Okay. So here’s the front frame of the N6700B. So to set this one up, we’re going to start
by pressing the Menu button. Scroll over to the System item and then choose I/O and DigPort.
From here, we go to Pins and set Pin 1 to Fault Out. And then we go back to the Pin
selection and choose Pin 3 and set that to Inhibit In. So right now, both supplies are
set to use the fault inhibit operation. So we’re going to force a fault
and see what happens.
So in order to show the functionality of the fault inhibit, we’re going to force a fault
on each of the two mainframes. So on the N6705A, what I'm going to do is set Channel 1’s
overvoltage protection to a value that’s lower than the maximum value that the unit
can put out, and then just program a value more than the overvoltage settings.
So you go to Settings, Protection. And we set it down to 10 volts. And you go back to
the Meter view. We’ll turn all our outputs on. And then we’re going to just go to
settings for Channel 1 here.
The default is 15 millivolts, so we’re just going to go out and set a level of voltage
that’s higher than 10, and go to Meter View, and you can see all our channels are in either OV,
which Channel 1 is, because the OV tripped, and the rest of the channels are Inhibit.
So now we’re going to just go and clear that protection on Channel 1. So set this
to 5 volts. Go back to Settings, Protection, Clear all outputs.
So everything’s back to normal.
So on the N6700B, we’re just going to show that this will shut off the N6705A.
We’re going to go to do the same thing. So we’re going to hit Menu, go to Protect on Channel 1.
The OVP, we’re going to set down to 10 volts. I then go back, back – just go back
to the meter. And I set the voltage to 11 volts. Hit Enter.
So you can see Channel 1 goes into OV. Channel 2, on this one, is inhibited. And the
two channels on top are inhibited. So when you’re done, just clear it, make sure everything
goes back to normal. Menu, Protect, we’ll go to Clear. Clear.
And everything’s back to normal.
So that’s just a quick tutorial on how to set the fault inhibit operation on the N6705A
and N6700B, so that when there’s a fault on one of them, you can shut the other one down.
If you have any questions about this, please feel free to contact us at Agilent,
and we’ll be glad to help you. Thanks for watching.