1 Introduction
3 Measurements
3.3 Power
Each successive press of the
button select a new range:
This document provides operating, maintenance and installation
instructions. This unit measures and displays the characteristics
of Single Phase Two Wire (1P2W), Three Phase Three Wire
(3P3W) and Three Phase Four Wire (3P4W) networks. The
measuring parameters include Voltage (V), Current (A),
Frequency (Hz), Power (kW/KVA/KVAr), Power Factor (PF),
Imported, Exported and Total Energy (kWh/kVArh).The unit also
measures Maximum Demand Current and Power, this is
measured over preset periods of up to 60 minutes.
The buttons operate as follows:
Selects the Voltage and Current display screens. In
Set-up M
ode, this is the “Left” or “Back” button.
Select the Frequency and Power factor display
screens. In Set-
up Mode, this is the “Up” button.
Select the Power display screens.
In Set-
up Mode, this is the “Down” button.
Select the Energy display screens. In Set-up mode,
this is the “Enter” or “Right” button.
Instantaneous Active
Power in kW.
User Manual
DRS-CT-3P-MOD-2T
DIN Rail Energy Meter for CT Connected
Three Phase Electrical Systems
DUAL TARRIF
Instantaneous Reactive Power in
kVAr.
It also comes with a complete comms capability with built in
Pulse and RS485 Modbus RTU outputs, configuration is
password protected.
3.1 Voltage and Current
Each successive press of the
parameter:
button selects a new
This unit is 1A or 5A current transformer operated.
Auxiliary powered.
Instantaneous Volt-Amps in KVA.
1.1 Unit Characteristics
Phase to neutral voltages.
The DRS-CT-3P can measure and display:
• Phase to Neutral Voltage and THD% (Total
Harmonic Distortion) of all Phases
• Line Frequency
• Current, Maximum Demand Current and Current
THD% of all Phases
• Power, Maximum Power Demand and Power Factor
• Imported, Exported & Total Active Energy
• Imported, Exported & Total Reactive Energy
Total kW, kVArh, kVA.
Phase to Line voltages
3.4 Energy Measurements
Each successive press of the
button selects a new range:
Current on each phase.
The unit has a Password-Protected set up menu for:
• Changing the Password
• System Configuration - 1P2W, 3P3W, 3P4W.
• Demand Interval Time
• Reset for Demand Measurements
• Pulsed Output Duration
Voltage THD% per phase
1.2 RS485 Serial
– Modbus RTU
RS485 serial port with Modbus RTU protocol to provide a means
of remotely monitoring and controlling the Unit. Set-up screens
are provided for setting up the RS485 port. Refers to section 4.8.
Current THD% per each phase.
1.3 Pulse output
Two pulsed outputs that can be set for active (kWh) or reactive
(kVArh) energy.
3.2 Frequency and Power Factor and Demand
Each successive press of the
button selects a new range:
2 Start Up Screens
The first screen lights up all
display segments and can be used
as a display check.
Frequency and Power
Factor (total).
The second screen indicates the
firmware installed in the unit and
its build number.
Power Factor of each phase.
Please note: Values may vary from
the numbers shown here.
Maximum Current
Demand.
The interface performs a self-test
and indicates the result if the test
passes.
Maximum Power Demand.
*After a short delay, the screen will display active energy
measurements.
Caution: Risk of
Warnings
Electric Shock
During normal operation, voltages hazardous to life
may be present at some of the terminals of this unit.
At voltages below that specified in the Range of Use
the meter may shut down. However, voltages
hazardous to life may still be present at some of the
terminals of this unit.
Installation and servicing should be performed only
by qualified, properly trained personnel abiding by
local regulations.
Ensure all supplies are de-energised before
attempting connection or other procedures.
Terminals should not be user accessible after
installation and external installation provisions must
be sufficient to prevent hazards under fault
conditions.
This unit is not intended to function as part of a
system providing the sole means of fault protection -
good engineering practice dictates that any critical
function be protected by at least two independent and
diverse means.
The unit does not have internal fuses therefore
external fuses must be used for protection and safety
under fault conditions.
Never open-circuit the secondary winding of an
energized current transformer.
This product should only be operated with the CT
secondary connections earthed.
If this equipment is used in a manner not specified by
the manufacturer, protection provided by the
equipment may be impaired.
Tariff 1 active energy in kWh.
Total active energy in kWh.
Please note the register is 9999999.9 display over two lines.
Date and Time can only be set via Modbus
Tariff 2 active energy in kWh.
Total reactive energy in kVArh.
Tariff 1 reactive energy in kWh.
Tariff 2 reactive energy in kWh.
