Andrea C

What is the state of interlock?
If interlock not satisfied, the max voltage is clipped/only a portion of 100V range can be used.

Closing the loop on this one.

Suggest updating firmware to latest (1.7.12b) ;  you are at 1.7.7b.

Even so, when using the integrating A/D, we are able to duplicate the issue with DMM7510 but not with DMM6500.
A bug has been logged for DMM7510 behavior.

Workarounds if using DMM7510:

First:  your trigger model operation is essentially sampling until told to stop;  You could get to essentially same outcome by making use of abort() command to stop an infinite count acquisition into a recycled finite sized buffer.

Second:  your trigger model operation will work and *TRG can be detected/used to stop it if the digitizing A/D is used instead of the integrating A/D.

Here is a code sample:

my_instr.write("reset()")
my_instr.write("errorqueue.clear()")

#comment out the use of integrating A/D
#my_instr.write("dmm.measure.func = dmm.FUNC_DC_VOLTAGE")
#my_instr.write("dmm.measure.range = 0.1")

​​​​​​​#use the digitizing A/D
my_instr.write("dmm.digitize.func = dmm.FUNC_DIGITIZE_VOLTAGE")  
my_instr.write("dmm.digitize.range = 0.1")
my_instr.write("dmm.digitize.samplerate = 10e3")
my_instr.write("dmm.digitize.aperture = dmm.APERTURE_AUTO")

my_instr.write("measure_buffer = buffer.make(12)")
my_instr.write("measure_buffer.fillmode = buffer.FILL_CONTINUOUS")

my_instr.write("trigger.model.setblock(1, trigger.BLOCK_BUFFER_CLEAR, measure_buffer)")
my_instr.write("trigger.model.setblock(2, trigger.BLOCK_MEASURE_DIGITIZE, measure_buffer, trigger.COUNT_INFINITE)")
my_instr.write("trigger.model.setblock(3, trigger.BLOCK_WAIT, trigger.EVENT_COMMAND, \
                                              trigger.CLEAR_ENTER, \
                                              trigger.WAIT_OR, \
                                              trigger.EVENT_DISPLAY)")
my_instr.write("trigger.model.setblock(4, trigger.BLOCK_MEASURE_DIGITIZE, measure_buffer, trigger.COUNT_STOP)")

Stands to reason that the SMU that is sinking the current needs to be lower potential than the external voltage source that the SMU is loading.

If need be, the SMU will transition to quadrant 3 (negative current and negative voltage) to allow the source current setpoint to be achieved.

See if the attached PDF helps.

What are you proposing to connect the 2651A to?

Can I ask:  what do you need the operating voltage to be?

I've uploaded a block diagram level of the SMU.

For your question about using it as a load, you will operate it as a current source with a voltage compliance limit.
To operate in quadrant 4 as a load, you would have the SMU source negative current.

The V-meter provides input to the voltage compliance limiting.

 

Hello,

That is very perplexing.

The USB0:: resource string is what I expect.
Does the front panel display the REM annunciator to indicated the remote connection has been made?
Also expect TSB will issue a reset().  For unknown reason, it is not successfully receiving a response from the 3706A.
Try a different USB A-B cable.  Also try different USB port on the computer if you have one.

With all Keithley related software, you should also have a utility program:  Keithley Communicator.
Try: close TSB and reboot 3706A.  Invoke Communicator and open the same USB0:: resource.

You and enter commands in the bottom frame, then hit the run button to send the command.
If you send something that sends back a response, press F2 or menu Command>Read Instrument Data.
Can you send *idn? command and read the response back?
What about sending reset() command.  And errors displayed on the instrument front panel?

Attached are some screen shots.
 

In Test Script Builder (TSB), the 'Open Instrument' icon in the Instrument Console should be enumerating and displaying the detected USB0:: type of VISA resource string for your model 3706A.
Do you have that?  If yes, select that and see if it can successfully connect.

The Wizard that you mention sounds like the Keithley Configuration Panel.  There is no requirement to do anything in the Config Panel to have TSB be able to see the USB0:: resources or to subsequently use the instrument from Python or similar.  The config panel allows you to associate a VISA resource with an IVI driver and also to assign alias to it to use when opening communication sessions.  The NI MAX software tool covers these same optional configuration aspects.

The 200 mA input is protected by a fuse (F2) rated at 440 mA, 1000 V (fast blow).

Dimension: 0.406 IN diameter X 1.375 IN length

Higher ranges are protected by fuse (F1) rated 11Amps, 1000V (fast blow).

Dimension:  0.406 IN diameter  X 1.5 IN length

These fuses are fairly popular in many different DMMs with amp measure.

Consider Fluke:
FUSE-440MA/1000VB1
FUSE-11A/1000V B1

Littlefuse FLU.440 and FLU011

Ferraz Shawmut FSM44/100 and FSM11

For an electronic load product type like the 2380 series, you are right to be aware of minimum operating voltage when sinking current.

However, a SourceMeter has very different analog architecture and does not have a similar concern.

If asking the SMU to source negative current (sink current into the HI terminal) you will also specify a (maximum) voltage compliance limit.  But the actual voltage that will develop between the HI to LO terminal is a consequence of the I*R drop external to the SMU and not due to internal I*R drops.
You could short HI to LO and have it sink current and it would be perfectly happy with the near to zero volt drop on HI to LO.

When sourcing current, the minimum allowed voltage compliance programmed value is 10mV.  But you'd set it this low only if you wanted to enforce this as a maximum voltage that the DUT should experience when forcing the current by the SMU.
Instead, you would set the voltage compliance to value larger than the expected I*R of the DUT.

You have it correct. 

For the 200 ohm range, the 1 year spec:  0.03% of value + 0.004% of range

For 10 ohm DUT measured on this range:
0.03% x 10 = 0.003 ohms
0.004% x 200 = 0.008 ohms

Total Error Budget:  0.011 ohms

If you make use of backplane relays or connect the DMM LO to the Output HI of bank 2, then you could measure between any two pins of bank 1 and bank 2.

If you have more than one 3723 card in the 3706A chassis, jumpering it to the backplane will be recommended way.

On rear of the 3706A is a DB15 connector that brings out the DMM HI and LO as well as the backplane relays HI and LO.
A small jumper on the DB15 could connect the DMM LO to the HI of backplane 3 (for example).
Each card (one by one) would need to close backplane #3 of MUX Bank 2 when a channel on that card is one of pins.

In the channel patterns, you can associate backplane relays with the card channel to have this automatic closure of the backplane relay with the channel.