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P G S 1 0 0 A N D PA S 1 0 0 | P R E S S U R E T R A N S M I T T E R S | O I/ P G S/ PA S 1 0 0 - E N R E V. A
. . .5 Transmitter wiring
Output (HART) transmitter wiring
communication board
connector for LCD
pushbutton for
0 (LRV setting)/
Span (URV setting) or
write protection
Figure 9 - Transmitter connection scheme
HART hand-held communicator may be connected at any wiring termination point in the loop, providing the minimum resistance is
250 ohm. If this is less than 250 ohm, additional resistance should be added to allow communications. The handheld terminal is
connected between the resistor and transmitter, not between the resistor and power source.
Application
Transmitter operated outside the potentially explosive atmosphere
Transmitter operated inside the potentially explosive atmosphere
WARNING - RISK OF EXPLOSION
If, when using transmitters with type of protection "intrinsic safety", an ammeter is connected to the output circuit or a modem
is connected in parallel while there is a risk of explosion, the sums of the capacitances and inductances of all circuits, including
the transmitter (see EC-type-examination certificate) must be equal to or less than the permissible capacitances and
inductances of the intrinsically safe signal circuit (see EC-type-examination certificate for the power supply unit).
NOTICE
For CSA ordinary location, the maximum current must be limited to 150 mA by fuse (slow blow) or by a current limiter.
Communication setup
The transmitter can be operated via a HART modem, using a PC or laptop. The HART modem can be connected to the transmitter in
parallel at any point in the signal circuit. Communication between transmitter and modem occurs via FSK signals that are
superimposed on the analog 4 to 20 mA output signal. This modulation occurs without averaging, therefore does not affect the
measuring signal.
Communication between transmitter and PC or laptop is only possible if the signal circuit is set up as shown in the following
figure. The resistance between the connecting point for the FSK modem and the power supply must be at least 250 Ω (including
internal resistance of the power supply unit). If this value is not achieved within the context of normal installation, an additional
resistor must be used.
!
CAUTION
SEE INSTRUCTION MANUAL FOR CABLE
TEMPERATURE RATING
power supply and
signal terminals
-
line load
cable entry
internal earth terminal
HAZARDOUS AREA
Permissible voltage range of power supply
Standard
from 10.5 to 42 V
from 10.5 to 30 V max (intrinsically safe)
resistor
+
-
optional
ground
power supply unit
handheld
terminal
SAFE AREA
With optional backlit LCD display
from 14.5 to 42 V
from 14.5 to 30 V max (intrinsically safe)
15
+
-
receiver unit
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