3
1 Safety Precautions
The manufacturer shall not be held responsible for failure to comply with the
instructions in this manual.
The equipment must be installed and serviced only by qualified personnel.
Never work alone.
Prior to any work on or in the equipment,isolate the voltage inputs and
auxiliary power supplies
，
short the secondary of all CT, but never short the
secondary of PT.
Always use a properly rated voltage sensing device to conform that all power
is off.
Risk of damaging device
◆
The voltage of the auxiliary power supply is beyond the rated range.
◆
The frequency of the power distribution system is beyond the rated range.
◆
The input polarity of the voltage or the current is wired improperly.
2 Description
General
This series multifunction power meters are designed to be used for the
measurement and calculation of electrical variables such as voltage, current,
frequency, power, power factor, energy, harmonic components,etc. in
low-voltage power distribution. It is capable of single-phase,two-phase,or
three-phase measurement and can be used in two-wire,three-wire,four-wire,
TN,TT,and IT systems.
Module
There are four interfaces on the meter for modules which are used to
extend functions. Please pay attention to the following points when installing
these modules.
a
）
Only one of communications modules
（
DM10-DM13
）
can be installed
onto meter ; Each module of DM11,DM12 and DM13 occupies two
interfaces;
b
）
Only one time memory module can be installed onto the meter;
