Dewetron PUREC, Техническое справочное руководство

Страница: 54 / 58

54
If there is no measurement category specified, the measurement input is not appropriate to be applied to a public
power grid.
Examples:
>
Rated input 600 V CAT II:
The measurement input can be connected to a public power grid within the category II as
long as the voltage of the grid does not exceed 600 VRMS. If there is a measurement category specified, the voltage
value stated is always considered to be RMS.
> Rated Input 600 VRMS: This measurement input is not intended to be connected to a public power grid. The input
would be suitable for measurements within an on-board power system of a train for instance.
Common mode voltage
' Common mode voltage ' indicates the highest possible voltage between the two input pins of a channel (e.g. IN+ and
IN-) and the reference potential (GND) without clipping the wanted signal.
ADC Isolation
IN+
IN-
V
Common Mode Voltage
In the very most cases the value of the ' common mode voltage ' corresponds to the value of the ' isolation voltage '.
Overvoltage protection
This value indicates the highest possible voltage which will not overload the input protection circuit when applied
between two pins of one channel.
Exceeding this value causes the damage of the measurement input in most every case, also other components inside
the measurement unit could be affected and it is furthermore a threat to life and physical condition (electric shocks,
burn).
ADC Isolation
IN+
IN-
Overvoltage Protection
V
DESCRIPTION OF VOLTAGE SPECIFICATIONS