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2
If you are using high voltage (
≥
30 V
rms
and 42.4 V
peak
or 60 VDC), please
read the following warnings:
Warning:
If high voltages (
≥
≥
≥
≥
30 V
rms
and 42.4 V
peak
or 60 VDC) are present, YOU
MUST CONNECT THE SAFETY EARTH GROUND TO THE
GROUNDING LUG. This complies with safety agency requirements
from UL 1244 and IEC 1010 and protects against electric shock when
the terminal block is not connected to the VXIbus chassis. To connect
the safety earth ground to the grounding lug, run an earth ground wire
in the cable from the signal source to the terminal block. National
Instruments is NOT liable for any damages or injuries resulting from
inadequate safety earth ground connections.
Equipment described in this guide must be used in an Installation
Category II environment per IEC 664. This category requires local level
supply mains-connected installation. Do not use this equipment to
measure voltages higher than 300 V.
SHOCK HAZARD: Only qualified personnel aware of the dangers
involved should open this unit. Disconnect all power before removing
the cover. If signal wires are connected to the module or terminal block,
dangerous voltages may exist even when the equipment is turned off.
Before you remove any installed terminal block, disconnect the AC
power line or any high voltage sources (
≥≥≥≥
30 V
rms
and 42.4 V
peak
or
60 VDC) that may be connected to the terminal block.
When using the terminal block with high common-mode voltages, you
MUST insulate your signal wires to prevent electric shock by using
300 V wire minimum. National Instruments is NOT liable for any
damages or injuries resulting from inadequate signal wire insulation.
The chassis GND terminals on the terminal block are for grounding
high-impedance sources such as floating source (1 mA maximum). Do
NOT use these terminals as safety earth grounds.