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Introduction
Product Description
5
Building Technologies
125-202
06/06/2017
Introduction
Product Description
MD-BMS and MD-BMED Power Meters monitor the voltage, current, power, power
factor, energy, and many other electrical parameters on single- and three-phase
electrical systems. Each MD-BMS and MD-BMED meter uses direct connections to
each phase of the voltage, and uses current transformers to monitor each phase of the
current. Information on energy use, demand, power factor, line frequency, and more
are derived from the voltage and current inputs.
The communications interface to the meters is an RS-485 serial or Ethernet connection
that uses the BACnet Master Slave Token Passing (MS/TP) protocol (default) or
Modbus protocol (user-selectable) for sending commands and retrieving data. A
separate remote terminal unit (RTU), Data Logger, or Building Management and
Control System is usually connected to the MD-BMS and MD-BMED meters to provide
data recording and trend logging plus a human interface or display.
The MD-BMS and MD-BMED meters are light-weight and compact enough to mount
within an electrical panel. They are used for long-term monitoring of electrical systems.
Up to 100 MD-BMS and MD-BMED serial meters can be connected to a single BACnet
MS/TP network for monitoring and recording power usage at multiple locations within a
single site. Up to 150 serial meters can be connected to a Modbus RTU network. The
total number of Ethernet units that can be connected is equal to the number of
available IP addresses. The actual number of device connections may be less,
depending on network bandwidth considerations.
There is a configurable digital pulse output port on the MD-BMS and MD-BMED that
can be used to output kWh, kVARh, or kVAh pulses to external devices, or to toggle on
and off to control a remote device or relay.
The MD-BMED Power Meter includes a backlit visual display that cycles through meter
information and real-time values of Volts, Amps, KW, KVA, Power Factor, kWh, and so
on. See
Appendix H.
Table 1: Product Numbers.
Part Number
Power Meter Kit Description
MD-BMS Power Meter Bundled Kits, Standard
MD-BMS-3-CTSC-100A
Meter with three 100A, split-core current transformers with 1" windows
MD-BMS-3-CTSC-200A
Meter with three 200A, split-core current transformers with 1" windows
MD-BMS-3-CTSC-400A
Meter with three 400A, split-core current transformers with 1.25" windows
MD-BMS-3-CTSC-600A
Meter with three 600A, split-core current transformers with 2" windows
MD-BMS-3-RC-16
Meter with three 4000A, 16” Rogowski Coil CTs, with 5" diameter windows
MD-BMS-3-RC-36
Meter with three 4000A, 36” Rogowski Coil CTs with 10” diameter windows
MD-BMED Power Meter, with Ethernet and Display, Bundled Kits, Standard
MD-BMED-3-CTSC-100
Meter with display and Ethernet, and three 100A, split-core current transformers with 1" windows
MD- BMED-3-CTSC-200
Meter with display and Ethernet, and three 200A, split-core current transformers with 1" windows