RMG TME400-VM, Руководство по эксплуатации

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2 Installation
Manual TME400-VMF · EN07 · December, 7
th
2020
39
If digital communication with the TME400 is required, it can be connected to the
RS485. The differential signals are obtained via data lines A and B under RS485
(
terminal block X6 ). Please pay attention to crossed signal lines and change the
connections if appropriate. If necessary, the data interface can be conditioned using
a jumper. Normally, the resistance is infinitely large (
ꝏ W
); for a point-to-point con-
nection or if the terminal device is part of a bus system, the resistance must be set to
120
W
.
Via "+ Uext" (external voltage supply, positive potential) and "- Uext" (external volt-
age supply, negative potential) the TME400 can be fed with 6-30 VDC in addition to
the internal battery (in non-Ex areas). "Earth" is used for internal voltage balance.
The power supply can be independent or in combination with the RS485 interface.
Anyhow, this supply voltage is required for communication via the RS485 interface.
Terminal block X6 also contains a digital input K1, which can be used to start, stop
and reset the totalizer; "+Input" is the contact input for positive potential, "-Input" the
contact input for negative potential.
Caution
In the Ex version, refer to the EC type approval certificate for the maximum
values for the current output and the RS 485!
Via "Pulse In" (
terminal block X5 ), pulses proportional to the flow rate at measure-
ment conditions can be read from an encoder with 1 or 2 frequency outputs (main en-
coder and second redundant encoder if required).
Encoder (sensor) 1 is connected to the terminals via "+S1" (positive potential) and
"-S1" (negative potential), encoder (sensor) 2 is connected to "+S2" and "-S2". This is
especially necessary for the TME400-VMF version operated at custody-transfer ap-
plications. The sensor types can be selected in coordinates Z26/27 (see chapter
4.3.3.7 Settings). Pulse input 2 is only active if a 2-channel counting mode is selected
(coordinate Z25).
Via "Pulse Out2" (
terminal block X3 ) pulses and redundant pulses can be output. An
alarm output can also be connected here. These six terminals combine the three digi-
tal outputs:
-Alarm: Alarm output negative potential
+Alarm: Alarm output positive potential
The alarm output works according to the closed-circuit current principle. The switch-
ing contact is closed in undisturbed condition.