Acromag TT339-0700, Руководство пользователя

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Model TT339-0700 4-Wire Isolated Frequency Transmitter w/USB
Acromag, Inc. Tel: 248-295-0880 [ 12 ] http://www.acromag.com
Optional Bus & Redundant Power Connections…
The figure below shows how to wire power to the optional bus terminal block when
mated to the bus connector. Note that power is wired to the rightmost bus
terminals on the right, or the left-most terminals on the left. Observe proper
polarity.
Earth Ground Connections
The module housing is plastic and does not require an earth ground connection. It
does include a special connector that makes functional contact with the DIN rail if
the DIN rail is grounded, but do not rely on this connection for earth ground. The
internal input, output, and power circuits are electrically isolated from each other,
allowing these circuits to be individually earth grounded as indicated. If the module
is mounted in a metal housing, a ground wire connection is typically required for the
enclosure and the metal enclosure’s ground terminal (green screw) should be
connected to earth ground using suitable wire per applicable codes.
See the Electrical Connections Drawings for Input, Output, and Power, and note the
position of earth ground. Earth ground should be applied at the input power minus
terminal (DC–). The input and output circuits are shunted to earth ground applied at
the power minus terminal via internal isolation capacitors.

Avoid inadvertent connections to earth ground at other points than those
indicated, as this could drive ground loops and negatively affect operation.
 A USB isolator is recommended when configuring or calibrating a transmitter to
avoid the ground loop that occurs if the input sensor is also earth grounded (PC
USB ports are commonly earth grounded and make contact with both the USB
signal and shield ground which is held in common to the input circuit ground of
the transmitter).
35mm DIN RAIL
TT300
Series
USB
DC
DC
DIN RAIL BUS POWER
YOU CAN OPTIONALLY CONNECT POWER
TO THE DIN RAIL BUS CONNECTOR ALONG
THE DIN RAIL USING THE OPTIONAL
TERMINALS AS SHOWN.
LEFT
RIGHT
+
+
+
–
–
– –
+
DC
DC
–
+
FUSE
+
–
DC SUPPLY
(12–32V)
*
MALE TERMINAL BLOCK
ACROMAG 1005-221
(RIGHT-SIDE CONNECTION)
CAUTION: DO NOT EXCEED 36VDC, OR
DAMAGE TO THE UNIT MAY RESULT.
IT IS RECOMMENDED THAT
SUPPLIES CAPABLE OF SOURCING
MORE THAN 2.5A TO THE UNIT BE FUSED
WITH A HIGH SURGE TOLERANT FUSE.
*
NOTE:
EARTH
GROUND
FEMALE TERMINAL BLOCK
ACROMAG 1005-220
(LEFT-SIDE CONNECTION)