Specifications

Principle of operation
The DM7 series resolver-to-digital decoder provides an
absolute encoder system in conjunction with any one of AVG
Automation's single-turn resolvers. As shown in the diagram
on the next page, the resolver rotor winding is excited from a
reference sinusoidal generator inside the DM7 unit. The ana-
log output signals from the resolver stator windings, after sig-
nal conditioning in the buffer amplifiers, are decoded to digi-
tal format in the ratiometric-tracking converter. The zero-off-
set entered from the front panel keypad is continuously added
to this digital value. The offset digital data is scaled, converted
to the digital format as selected from the keypad and displayed
on the front panel of the unit. The position information is also
made available in a parallel format for external devices, such as
PLC remote displays, etc.
Versatile
Programmable Full-Scale Offset for Easy Set-Up
The resolver can be mounted on the machine without any
concern for mechanically aligning the resolver zero to the
machine zero. Once the resolver is coupled to the machine
shaft, the only thing you have to do is to bring the machine to
a known position, say home position, and set an offset number
from the front panel keypad until the display reads zero posi-
tion. This is especially useful during initial start up in that it
reduces the set-up time. The offset can also be used to com-
pensate for any machine wear.
Programmable Resolution: 20-4096 Counts-
per-Turn
The programmable scale factor feature provides you the flexi-
bility of selecting the resolution in the field. Now you do not
have to worry about defining the resolution at the time of
ordering the unit. The scale factor can be programmed from
the front panel and can be any number between 19 and 4095
resulting in resolution of 20 to 4096 counts per turn. This fea-
ture allows you to scale the position to desired engineering
units (inches, mm, etc.), if required.
THE DM7 DECODER
DM7 PROGRAMMABLE RESOLVER
DECODER
SINGLE-TURN, SINGLE-CHANNEL
The most versatile resolver-to-digital decoder
◆ Fully absolute position, no loss of position under
any situation
◆ Incredibly small size; only 9 sq.in. panel space
◆ Full-scale programmable zero offset for easy set-up
◆ Programmable resolution; 20-4096 counts-per-turn
◆ Front panel selectable output formats: BCD, Binary,
or Gray code
◆ Built-in PC sync circuit permits interface to any PLC
◆ Built-in digital tach and over-, under-speed switch
◆ Direction output and zero marker pulse
◆ Self-diagnostics with fault output
◆ Optically isolated outputs
◆ Highly noise immune ratiometric tracking
converter
◆ Extremely rugged and reliable resolver as position
transducer
A-27
800-TEC-ENGR
www.avg.net
Position Transducers/Sensors
SECTION
A