UPS connection via USB

For this function, firmware 2.26 or later is required.

Hardware: CS141HW161 with USB port

UPS systems increasingly require a USB interface for communication. With firmware 2.26, the CS141 now also offers the option of integrating UPS systems directly into an existing network via USB.

Note: First activate USB or set up the UPS?

The USB port and the UPS model selection are largely independent of each other - you are free to decide whether you first activate the USB port or connect and set up the UPS:

In any case, the UPS will only provide data once both settings have been carried out

The configuration is carried out in two steps, which can be performed in any order

First Setting up the UPS model

Open the menu:

Devices>UPS>Setup

Select the UPS model that is connected. The CS141 will automatically load the recommended values. Click Apply to save the UPS model setup.

Second Switching to USB-Mode

Now, open the system menu:

Devices > Setup.

Enable the USB interface, and slide the switch for UPS to ON position.

The CS141 will disable the serial interface (COM 1 is set to “none”) and enable USB interface for the UPS.

Please note: Simultaneous operation (USB and serial connection at the same time) with different devices is technically not provided by the UPS system itself!

UPS with center tap

Tipp:

The CS141 will provide this function in case of using a UPS with center tap support.

What is a ‘Center Tap‘

Modern UPS systems divide their single battery pack into two symmetrical pack parts and use a center tap. By using a center tap, they increase the nominal efficiency:

Measurement difference and charge difference

The measurement when using a center tap is basically a way of looking at it:

You measure from the UPS to the center tap and then on the other side from the center tap back to the UPS. Since the batteries all remain connected in series, two phenomena can be noticed when there are voltage problems: If a battery has a problem on the negative string, the general voltage for all batteries will decrease.

The individual measurements of the string will show more details:

1. The total voltage for all batteries drops.
2. Measured from the UPS to the center tap at the negative string will indicate the missing string voltage.
3. Measured from the center tap back to the UPS on the positive side shows that all batteries work as desired.

Ideally, a UPS should be able to indicate which specific battery string is experiencing a problem, eliminating the need to inspect all batteries individually.

Where the problems with the UPS start

A UPS has limited diagnostic capabilities in this context. Although it can detect variations in measurement data, its ability to interpret this data is constrained. 

Batteries age at different rates—even when used under identical conditions—causing the data from individual battery branches to gradually diverge over time. Once a defined threshold is crossed, the UPS typically reports a general battery fault; however, this often occurs too late to prevent failure.

It is no longer possible to estimate how many batteries have hidden defects due to the imbalance. Most of the time the UPS fails due to the hidden drifting process in an unfortunate moment.

The CS141 can monitor precisely these “hidden drift processes” and issue warnings and alarms in good time if there are questionable values. This provides maintenance personnel with valuable lead time to carry out necessary service work before a critical failure occurs.