Delta Controls DPR-2000 - Manual (Page 20)

A 18 IOM-DPCDPR-A: FEB 2014
8.3.2. The DPR-2000GALW transmitter can also be fitted with an adapter (Fig.17) creating a C-type connector,
designed for installation on a 3-valve or 5-valve manifold. Delta Controls can also supply ready transmitters
mounted on valves.
8.4. DPR-2000YALW. Installation and connections
The DPR-2000YALW level probes installed in places where liquid levels are measured in closed tanks, with
access to medium from top of tank as fig.15 and 10.2.6. Level probes should be installed in a vertical position.
Pressure may be transmitted to the installed device only after checking that it has a measurement
range which properly corresponds to the value of the measured pressure, that gaskets have been
properly selected and fitted, and the connectors have been properly screwed tight.
Attempts to undo the screws or fixing connector pipes on a transmitter under pressure may
cause the medium to leak and create hazards for the personnel.
When disassembling the transmitter, it is necessary to disconnect it from the process pressure or
bring the pressure to atmospheric level, and to take particular care and precautions in case of
media which are highly reactive, caustic, explosive or otherwise hazardous to personnel.
If necessary, rinse out this part of the system.
Transmitters with flange diaphragm seals are to be installed on the corresponding counter flanges on the
facility.
It is recommended that the user matches the screw joints material to the pressure, temperature, flange
material and seal to ensure tightness of the flange joint in the expected operating conditions..
Screws complying with ISO 261 are to be used for flanges used in the DPC..., DPR... transmitters.
Additional data concerning the diaphragm seals are specified in the “DIAPHRAGM SEALS” catalogue cards.
9. ELECTRICAL CONNECTION
9.1. General recommendations
9.1.1. It is recommended that twisted pair cabling be used for the signal lines. If the transmitter and signal line
are subject to a large amount of electromagnetic interference, then shield pair cable should be used. The signal
wires should not run alongside network power supply cables or near to large electrically-powered devices.
The devices used together with the transmitters should be resistant to electromagnetic interference from the
transmission line in accordance with compatibility requirements. It is also beneficial to use anti-interference
filters on the primary side of the transformers, the power supplies used for the transmitters and apparatus used
in conjunction with them.
9.1.2. Wet or rising damp inside transmitter can cause its damage.
When the isolation of the wires in the packing gland is ineffective (for example, when single
wires are used) the opening of the gland should be carefully sealed with an elastic sealing
compound to obtain IP66 protection. It is useful to form the segment of the signal wire leading
to the packing gland into a protective loop to prevent condensation from running down in the
direction of the gland.
9.2. Electrical connections for DPC..., DPR...
The DPC..., DPR... transmitters are to be connected as shown in fig. 2a – 2d.
In DPC..., DPR... transmitters, a 240Ω resistor is permanently fitted in series in the transmitter’s current
circuit and blocked up with jumper between –> and as shown in fig.2a and 2b.
When the resistance in the current loop is lower than 240Ω it is necessary to jumper disassemble to
Hart communication.
9.3. Protection from excess voltage
9.3.1. The transmitters may be in danger from excess voltage caused by connection faults or atmospheric
electrical discharge.
Protection from excess voltage between the wires of the transmission line is provided by TVS diodes installed in
all types of transmitter (see the table, column 2).
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