Why is the Ground signal coupling option not present in new models?

Hi,<br> <br> I work in an experiment that uses one current transimpedance amplifier in low mV/div scales. Typically, we ground the channel before turning on or off the amplifier power supply to avoid transients going to the oscilloscope. &#160;<br> <br> We used an oscilloscope TDS2024 which failed and was replaced by a new model TBS2204B. The old oscilloscope could ground each channel (Ground/AC/DC), but the new one only has AC/DC signal coupling options. So, <strong>do you know why the ground option is not more necessary in the new model?</strong> Is the TBS2204B grounding the input signal when the channel is disabled (I mean, when pushing the channel button until the signal disappears from the screen), or does the signal can still go through the oscilloscope circuits?&#160;<br> <br> I have searched extensively in the manual and on the web without success. So, I appreciate any help you can provide

Hi,<br> <br> The oscilloscope is rated for 300 Vrms CATII and 450 Vpeak transients over its entire input range, including the low mV/div scales.<br> If you are below these values, then I would not worry about transients damaging the oscilloscope. If your transients are above 450 Vpeak, then ground coupling wouldn't fix your issue.

Thank you for your response, Afonso. The transients are quite lower than 450 Vpeak, so it is good to know that I don't have to worry :)