Description
HD 2004T and HD 20V4T are microprocessor pressure transmitters, the first one hav-
ing a current output (4÷20 mA) and the second one a voltage output (0÷5V, 1÷5V or
0÷10V).
The sensitive element consists of a bridge of piezoresistive resistances laid on a
ceramic diaphragm. When changing the applied pressure, the bending of this
diaphragm causes a linear and proportional change of the bridge resistances.
The stainless steel case (30 mm diam.) includes both the sensor and the electronics:
unscrewing the base equipped with faston connectors, you access the keys to adjust
the upper and the full scale. A LED helps the user during the calibration procedure.
1
A
/
" BSP threaded connection and a slot on the case for a 24 mm wrench are provid-
4
ed to connect the transmitter with the plant under pressure. On the other side, a 3/4-
pole (depending on models) male faston connector, the relevant outlet and a PG7 cable
gland pursuant to DIN 43650 are provided to grant the electrical links.
Technical Specifications
Output Signal
Current
Voltage
Pressure range
Overpressure limit
Up to 250 bars
400 nominal bars
600 nominal bars
Sensor
Material in contact with the measuring fluid
Fluid in contact with the diaphragm
Operating temperature
Power supply voltage
Span and full scale adjustment
Accuracy (linearity, hysteresis and repeatability)
Gain sensitivity to temperature changes
(@ 25°C)
Zero sensitivity to temperature changes
(@ 25°C)
Process connection
Electrical connection
Housing made of
Size
Weight
Load resistance for HD 2004T models...
(see Fig.2)
Load resistance for HD 20V4T models...
Response time
Installation and connections
HD 2004T... and HD 20V4T... transmitters can be installed in any position. Open the
female connector to make the electrical connections (see fig.3).
Transmitter Calibration
The transmitter output is factory-calibrated, thus, no user's operation is generally
requested.
Current output transmitters supply 4 mA at scale beginning and 20 mA at full scale;
0...5V, 1...5V and 0...10V voltage output transmitters generate 0V or 1V at scale begin-
ning pressure and 5V or 10V at full scale pressure.
To adjust these values (within a ±10% of the range), you need the following instru-
ments:
• a pressure calibrator with an adequate full scale;
• a voltage generator with the value included between 10 and 30Vdc;
• a 25 mA full scale precision ammeter or a voltmeter having an adequate scale (5.5 or
11V, at least, according to the model).
Procedure
1) Connect the HD 2004T... or the HD 20V4T... to the pressure generator using proper
gaskets, if necessary.
2) Unscrew the plastic ring nut at the bottom of the transmitter without turning the
faston connector (see fig.5).
Behind the plastic ring nut there is the calibration circuit with the keys and the LED
as shown in fig.6.
3) Follow the indications shown on fig.7 to make the electrical connections and insert
the connector into the transmitter.
4) Apply the upper range pressure, and press ENTER to calibrate the first point: the
programming LED lights up to indicate that the first calibration of the transmitter is
being carried out.
s
5) Ad just the output value using the
6) Press ENTER to confirm data: the programming LED will turn to off.
To calibrate the second full scale current or voltage value, repeat the procedure from
item 4) to 6), applying the full scale pressure.
7) Screw the ring nut and check that the ground terminal fits its seat and touches the
transmitter metallic ground: the calibration procedure is over.
4...20 mA (HD 2004T...)
0...5V (HD 20V4T... 1), 1...5V (HD 20V4T... 2),
0...10V (HD 20V4T... 3)
1, 2.5, 4, 6, 10, 16, 25, 40, 60, 100, 160,
250, 400 and 600 absolute bars
1, 2.5, 4, 6, 10, 16, 25, 40, 60 relative bars
Twice the rated value
750 bars
750 bars
Piezoresistive
Alumina
Gas or liquids
-30...+80°C
10...30Vdc
(15...30Vdc for models having 0...10Vdc output)
±10% through up, down and enter)
≤ ±0.4%F.S.
≤ ±0.008%F.S. between 0 and 70°C
≤ ±0.012%F.S. between -30°C and 0°C
and between 70°C and 80°C
≤ ±0.04%F.S.
1
/
"BSP male
4
3/4 -pole faston male connector
+ DIN 46350 female connector (outlet)
AISI 304 stainless steel
∅ 30x90 mm (included DIN 43650 connector)
190 g
(Vcc-10)
= 636 Ω to 24 Vdc
R
R
=
Lmax
Lmax
22 mA
≥ 10K
R
L
1 sec. (Time required to achieve the 63%
of the final variation)
t
and
keys.
Notes
A) To avoid storing wrong data, HD 2004T... and HD 20V4T series transmitters are pro-
vided with a protection system that automatically quits the calibration procedure
without editing stored data, if more than 45 seconds elapse since the last key has
been pressed,.
B) HD 2004T... and HD 20V4T... series transmitters automatically acknowledge the
applied pressure as upper range pressure, if it does not exceed 15% of the nominal
pressure, and as full scale pressure if it exceeds the 40% of the transmitter nominal
pressure.
HD 2004T... and HD 20V4T... series pressure transmitters can be connected with Delta
Ohm HD 9022 Single Input Configurable Controllers / Panel Meters or with Double
Input DO 9404 ones.
Caution: the pressure transmitter has a
attentively that the connection fitting is pressure-sealed when installing the transmitter.
If needed, use proper gaskets.
Be careful when installing the transmitters into under-pressure con-
tainers or into pipes. Pay attention in selecting the full scale flow: a
mistake, besides damaging irreparably the transmitter, might cause
even heavy physical injuries to the operator and damages to things
and equipments. Mount always a stop key before the transmitter and check that
no peak or abnormal and unexpected rushes of the fluid under pressure occur on
the plant.
Order codes
FULL
RELATIVE
SCALE
Ref.: atmospheric pressure
1 bar
HD 20...4T- 1 BG...
2.5 bar
HD 20...4T- 2 B5G...
4 bar
HD 20...4T- 4 BG...
6 bar
HD 20...4T- 6 BG...
10 bar
HD 20...4T- 10 BG...
16 bar
HD 20...4T- 16 BG...
25 bar
HD 20...4T- 25 BG...
40 bar
HD 20...4T- 40 BG...
60 bar
HD 20...4T- 60 BG...
100 bar
160 bar
250 bar
400 bar
600 bar
HD 20V4T
3
1
/
" BSP male threaded connection. Check
4
1 = 0...5V
2 = 1...5V
Output:
3 = 0...10V
none = 4...20 mA
A = Absolute pressure
G = Relative pressure
B = bar
Nominal full scale (bar)
1-2.5-4-6-10-16-25-40-60 relative or absolute bar
100-160-250-400-600 absolute bar
0 = Current
Type of output:
V = Voltage
ABSOLUTE
ABSOLUTE
Ref.: vacuum c.a.
Ref.: 1 bar c.a.
HD 20...4T- 1 BA...
HD 20...4T- 2 B5A...
HD 20...4T- 4 BA...
HD 20...4T- 6 BA...
HD 20...4T- 10 BA...
HD 20...4T- 16 BA...
HD 20...4T- 25 BA...
HD 20...4T- 40 BA...
HD 20...4T- 60 BA...
HD 20...4T- 100 BA...
HD 20...4T- 160 BA...
HD 20...4T- 250 BA...
HD 20...4T- 400 BA...
HD 20...4T- 600 BA...