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I recently bought a new GDS-1052-U oscilloscope. I read a few pages from the oscilloscope manual and I found that the maximum input voltage is 300Vpeak.

I have a question regarding the maximum input voltage: Is 300V peak the maximum voltage input for 10V/div or for 2mV/div using a 1x probe and AC coupling?

Will the oscilloscope be damaged if I set the vertical voltage to 2mV/div and connect the 1x probe to 200V peak? I know that the 200V peak voltage cannot be displayed on the screen if the vertical voltage is 2mV/div, but I want to know what can happen?

The last question: What is the maximum DC input voltage, using a 1x probe and DC coupling?

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The maximum voltage is ±300V, period.

It doesn't matter what the settings on the scope are, or whether the voltage is AC or DC.

Any voltage less than that will not damage the scope, but what you see on the display may or may not be useful, depending on the settings.

You can use a 10× probe to measure higher voltages — up to whatever the probe is rated for — but if you ever switch the probe to 1× while doing so, you'll be violating the scope specification.

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  • \$\begingroup\$ Thanks for the reply. What means "offset range bandwidth limit" ? I saw this in the manual: imgur.com/LB1cvYr \$\endgroup\$ – mike_mike Jan 21 '18 at 18:02
  • \$\begingroup\$ So the "offset range bandwidth limit" doesn't mean the maximum input voltage ? \$\endgroup\$ – mike_mike Jan 21 '18 at 19:03
  • \$\begingroup\$ "Offset range bandwidth limit" is actually two separate specifications: "Offset Range" (the top line) tells you how far the trace can be offset from zero for the various vertical scale settings. "Bandwidth Limit" (the bottom line) simply tells you the -3dB bandwidth of the scope overall. \$\endgroup\$ – Dave Tweed Jan 21 '18 at 19:17
  • \$\begingroup\$ Can you be more explicit ? I don't really understand. The offset range bandwidth limit is the maximum voltage allowed at the input of the oscilloscope or the maximum input voltage is 300Vpeak ? \$\endgroup\$ – mike_mike Jan 21 '18 at 19:22
  • \$\begingroup\$ For example, on any of the ranges from 2mV/div through 50mV/div, you will be able to bring any voltage between +/-0.4V to the center of the screen using the vertical offset control. That's what "offset range" means. \$\endgroup\$ – Dave Tweed Jan 21 '18 at 21:31
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Dont confuse multiple specs. Separate them. enter image description here

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See below datasheet on p139 enter image description here

The DSO measurement capability spec is 300V AC+DC , THIS MEANS that you can measure 300V off the screen by using the vertical offset dial.

A different item is the human safety limit " 300V CAT II" but is capable of withstanding the standard 2.5kV impulse test

This assumes the x1 probe.

There are safety measurement zones called Category I,II,III,IV... **

This instrument is only rated for CAT II. Beyond this can be fatal to the user at the same voltage.

  • CAT I is safe low voltage & current.
  • CAT II is 300V max but limited to protected residential outlets. but IEC certification tests include exposure to 2.5kV impulse tests.
  • CAT III is inside the breaker panel ( ie. connected to grid with greater risks)
    • which is restricted for use with this instrument, even though it is the same voltage.

** This is due to ARC Flash prevention limits due to energy , current limit and protection categories to prevent fatal measurements in CAT III e.g. spontaneous human combustion. ( sorry to be so graphic )

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  • \$\begingroup\$ Does even Category II guarantee that the instrument will not be damaged by the specified overload, or only that there is no danger of shock, fire, or false negative readings? \$\endgroup\$ – rackandboneman Jan 21 '18 at 21:04
  • \$\begingroup\$ 300V CAT II means no damage to instrument and can actually measure 300V and display with offset \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jan 21 '18 at 21:44
  • \$\begingroup\$ "The DSO measurement capability spec is 300V AC+DC , THIS MEANS that you can measure 300V off the screen by using the vertical offset dial." So this means that if I connect the input to 200V AC + DC using an 1x probe and the scope configured on 2mV/div then the scope will not be damaged ? \$\endgroup\$ – mike_mike Jan 22 '18 at 6:50

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