Product Info

On-Demand 1.2 Overview 3
Technical Brief
Users may find additional information on water MTUs in the Water MTU Field
Guide, Y20376-TRD.
Refer to the MTU Installation Instructions Technical Brief, Y20355-TEB for more
information on MTU installations.
All Aclara RF ™ MTUs in a single AMI system use a unique FCC-licensed
frequency for one-way transmission of readings. The frequencies we use fall in the
range of 450-470 MHz. Aclara works with the utility to find a frequency that has
the least local interference possible and to have that frequency licensed with the
FCC for the client’s geographical area for 10 years. If interference should arise, the
FCC will address any unlicensed use.
N OTES There are only two authorized antenna options: the internal antenna etched
into the printed circuit board (PCB) and the external antenna, MicroAnt
(Aclara part number 073-3002.
Maximum gain allowable is 3dBi.
The MTU also uses a second licensed frequency, within the same range, for a
two-way communication with the DCU. This frequency is used primarily for time
synchronization from the DCU. Having the entire system synchronized to within
one minute allows for system consumption snapshots for the amount of water
being used across the network at any one time.
The signal from Aclara’s standard range MTU typically reaches from a half-mile
to a mile, depending on terrain. Aclara’s extended range MTU can reach about
twice that distance, or up to two miles.
Once an MTU is installed at a meter site, it must be activated. This is performed
using a programming device such as a laptop or tablet computer and Aclara STAR
Programmer software. (For more information on Aclara’s STAR Programmer,
please refer to the STAR Programmer Software User Guide, Y20348-TUM).
The technician installing the MTU enters some basic information such as the type
of meter and its location when programming the MTU. The software
communicates electromagnetically with the circuitry in the MTU and activates its
radio transmitter. This process creates a programming record for each MTU
programmed. At the end of the day, the installer uploads these programming
records to AclaraONE, so the system will have all the information for each MTU.