Incorrect voltage readout on Driver Station

[Kevin Wang]

Whenever we are connected to the robot, the driver station always reports a voltage of 17.68 volts. This issue has been observed on multiple laptops. Has anyone else observed this issue?

[kinganu123]

Just thought I'd add to the problem:
We always get somewhere between .05-.07 volts
This happened like 3 or 4 days after the switch to SmartDashboard

[Joe Ross]

Originally Posted by Kevin Wang

Whenever we are connected to the robot, the driver station always reports a voltage of 17.68 volts. This issue has been observed on multiple laptops. Has anyone else observed this issue?

What programming language are you using?

Originally Posted by kinganu123

Just thought I'd add to the problem:
We always get somewhere between .05-.07 volts
This happened like 3 or 4 days after the switch to SmartDashboard

Is the battery monitoring jumper installed on the analog breakout?

[Alan Anderson]

The NI 9201 analog input module is only supposed to be capable of reading a maximum of ten volts. The Analog Breakout has a 680ohm/1k voltage divider in the circuit to reduce the battery voltage to something within range. The calculation of the number to display compensates for this. If somehow you're getting full battery voltage on the NI 9201 input, and if it is somehow returning that value (which is greater than it is specified to handle), you'd see about 17.68 volts on the display. An open circuit in the 1k resistor path would do it.

Your team probably has a spare Analog Breakout (one came in the kit this year and last year, and there were two with the first year's cRIO). Try swapping out the one you're using now and see if the voltage display becomes correct.

[LV1601]

This happened to us before just try to install the jumper again if it not perfect then it might read wrong.

[kinganu123]

No idea what the heck happened, but our bot hit a locker (don't worry the bumpers were on) and it started magically working
I guess the impact somehow fixed the wiring

[cilginbilgin]

Another thing to add that issue our driver station always reads 0 voltages whenever we are connected to robot.

Does someone know how to fix this problem?

[Vikesrock]

Originally Posted by cilginbilgin

Another thing to add that issue our driver station always reads 0 voltages whenever we are connected to robot.

Does someone know how to fix this problem?

Common causes of this are not installing the jumper on the Analog Breakout and not powering the Analog Breakout board.

The jumper should be installed on the outside two pins of the 3 pin header.

The Analog Breakout requires 12V power from the Power Distribution board in order to run.

The Analog Breakout Datasheet provides more detail if you need it:
http://www.usfirst.org/uploadedFiles...out%281%29.pdf

[wireties]

Ours is reading zero also. I have swapped analog modules and breakouts and the jumper is in the correct position. We are playing with custom dashboard code at the moment and getting message errors. Could that be messing it up?

TIA

[Alan Anderson]

Originally Posted by cilginbilgin

...our driver station always reads 0 voltages...

Originally Posted by wireties

Ours is reading zero also.

It would greatly help us help you if you could take a clear photo of your analog breakout while the problem is occurring and post it here, showing the jumper and the wiring connected to it.

[wireties]

photo attached - sure looks correct

[Alan Anderson]

Originally Posted by wireties

photo attached - sure looks correct

It looks okay...except for the lack of any indication that there is actually power applied. There's a green LED that ought to be lit. What voltage do you see using a meter on the white Wago connector?

[wireties]

Originally Posted by Alan Anderson

It looks okay...except for the lack of any indication that there is actually power applied. There's a green LED that ought to be lit. What voltage do you see using a meter on the white Wago connector?

Sorry - the power was not on - the green LED is on when power is applied - we see 12.07V on the wago connector. It must have something to do with the dashboard packet format not matching (because we are customizing it).

TIA

[Greg McKaskle]

Customizing a dashboard will not break the robot battery voltage communications. They are very independent.

Greg McKaskle

[Alan Anderson]

The problem became obvious once I realized what to look for.

Keith, your NI 9201 module is in Slot 8 of the cRIO chassis. It needs to be in Slot 1, at the end nearest the Ethernet ports and power connector.