Rigol DM3068, Service Manual

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RIGOL
Service Guide for DM3068
IV
on the rear panel provides the current passing through LO Sense/200
mA up to 500 mA protection.
3
．
Current input (10 A and Sense/200 mA) terminals
10 A and LO terminals are used for current measurements of 2 A and 10 A. The
maximum current going through the 10 A terminal is limited to 10 A by the
internal fuse. LO Sense/200 mA and LO terminals are used for current
measurements ranging from 200
µ
A to 200 mA. The maximum current going
through the LO Sense/200 mA terminal is limited to 500 mA by the internal
fuse.
NOTE:
In order to prevent the fuse from blowing out and protect the
multimeter, please use the current input terminals according to the
following requirements:
1) Do not connect the 10 A and LO Sense/200 mA input terminals into the
current measuring circuit at the same time.
2) Only use 10 A and LO terminals for measurements when the measured
current AC+DC RMS value goes within 200 mA and 10 A.
3) Select a proper current input terminal according to the estimated current
magnitude before connecting the multimeter to AC supplies if you want to
use current measurement.
4) The current into the 10 A terminal cannot exceed 13.5 A, otherwise it will
blow out the internal fuse; while the current into the LO Sense/200 mA
terminal cannot exceed 650 mA, otherwise the current input fuse from the
rear panel may be blown out.
IEC II Overvoltage Protection
In order to prevent electric shock, DM3068 provides overvoltage protection for
line-voltage mains connections meeting both of the following conditions:
1
．
The HI and LO input terminals are connected to the mains under Measurement
Category II conditions defined below.
2
．
The mains are limited to a maximum line voltage of 300 VAC.
WARNING: IEC II includes electrical devices connected to mains through an outlet
from the branch circuit. Such devices include most small appliances, test equipments
and other devices inserted into a branch socket.
DM3068 may be used to make measurements with the HI and LO inputs connected
to mains in such devices (up to 300 VAC), or to the branch socket. , the HI and LO
inputs of DM3068 cannot be connected to mains of permanently installed electrical
devices such as a main circuit-breaker panel, sub-panel disconnected box or wired
motors. Such devices and circuits are readily to beyond the protection of DM3068.
NOTE: Voltages above 300 VAC may be measured only in circuits that are isolated