Part 1 of R&S NGP814 Power Supply - Review

 

Overview and User Interface

 

Compared to many other devices I have used the user interface of the NGP814 is by far the most user friendly. It offers easy access to all settings and designed with ease of navigation between menus in mind.

I tried to cover most of the menus in the photos below (some menus are seen twice, while I scrolled down to show all the option to select from).

 

A- Device menus

First is the generic device settings, these options are for the unit as whole.

B- Channel menus

The settings under each channel are channel specific (some limits can vary depending on the channel max voltage rating 32V / 64V).

It is worth to note that the touch screen adds a very nice feel to operating the device, crisp clear and very smart phone like hold and drag functionality.

Note: These screenshots were taken before the firmware was updated, the only difference I noticed after the update is that the device menu (first photo) now shows the option to go to graphical view.

 

Firmware Update

Upgrading the device firmware was very straight forward and exactly as documented.

Everything was as expected and no issues were encountered. The screenshots below show the update process.

 

 

 

 

 

Calibration & Channel adjustment

User calibration wasn't straight forward in the documentation. I assumed that there would be a wizard to guide the process, ended up going through all the SCPI commands.

The voltage and current offset calibration were found in a section called "Adjustment" in the user manual. Not sure if this naming convention is typical of R&S instruments, but it was new to me and I only came across it because I am doing the road test, I assume if I bought the instrument I might miss this section and end up preparing a script to calibrate if needed, which would have taken some time to do.

 

Part 1: Analog In Adjustment.

 

I did not try this because it requires an external precision reference power supply, I have a couple units but none of them is a precision device or been recently calibrated.

 

Part 2: Channel adjustment.

 

 

The adjustment wizard is found in the channel settings. As recommended I connected a 10mohm shunt resistor with a 1% tolerance for current adjustment, the instructions does not specify a power rating for the resistor but it states that it needs to be rated for a minimum of 25A. The on-screen instructions were clear and easy to follow, it displayed warnings for safe operation and states that the supply must be in operation for at least 30 minutes before starting, to allow the circuitry to reach stable operation.

 

 

The channel adjustment process starts by applying low voltage then higher voltage and asks for measured values. It does not show what the voltage applied is supposed to be, one thing that did not seem right is that in both cases I measured a voltage across the shunt resistor of about 76mV. After that a pop up message appears that says the following part will be done automatically, it also says "Please leave the connection open", after pressing proceed I got an error message saying that channel adjustment failed.

I repeated the same process on other channels before giving up and still got the same error message.