OJ Electronics PTH-3-DF Serie Instructions page 7

measured as % of
full-scale pressure
range using square root
calculation.
k-factor 0.001 to 9999
TECHNICAL DATA
Supply voltage ...................24 V~/=, ± 15%, 50/60 Hz
Power consumption ........................................... 0.5 W
Output ...............................................0-10 V=, 2-10 V=
Accuracy*
PTH-3202/3203 ........0.5 %×MV*+0.3 %×SR*+2.5 Pa
PTH-3502..................0.5 %×MV*+0.3 %×SR*+5.0 Pa
Maximum pressure
PTH-3202/3203/3502 .......................................30 kPa
Maximum load
0 – 10 V= ...........................................................>2.5kΩ
0 – 20 mA ........................................................ <=450Ω
Dampening (selectable) ............................0.4 s or 10 s
Housing dimensions (h×w×d) ...............91×75×38mm
Cable dimension ..........................................ø3-10 mm
Connection
PTH-3202/3203/3502 ........................ 4 x Screw term,
Pressure tubes .........................................2 × ø6,2 mm
Environment data
Storage temperature ........................... -40°C to +70°C
Operating temperature -20°C to +40°C (continuous)**
-30°C to +70°C (short-term)***
Operating humidity ...................... 10%RH to 95%RH,
Operating altitude ........................................... ≤2000m
Enclosure rating .....................................................IP54
Weight ..................................................................110 g
*Note: MV = Measured Value / SR = Set measuring
range
**Note: Ambient temperature affects the LCD
display speed and contrast
***Note: DC Supply is recommended if the
operation temperature exceed 40°C
TECHNICAL DATA PTH-3502-DF
Full-scale pressure range:0 - 5000 Pa
Measurement ranges,
pressure: 0.0.. + 500.0 Pa
0.0.. + 1000 Pa
0.0.. + 1600 Pa
0.0.. + 2000 Pa
0.0.. + 2500 Pa
0.0.. + 3000 Pa
0.0.. + 4000 Pa
0.0.. + 5000 Pa
Measurement ranges,
flow: 1.00 m³/s, 3.00 m³/s,
5.00 m³/s, 10.00 m³/s,
30.00 m³/s, 50.00 m³/s,
100,0 m³/s, 100.0 m³/h,
300.0 m³/h, 500.0 m³/h,
1000 m³/h, 3000 m³/h,
5000 m³/h, 9999 m³/h,
30.00 m³/h x 1000,
50.00 m³/h x 1000,
99.99 m³/h x 1000.
The unit m³/h can be
replaced by l/s or m³/s.
Square root output: In the flow range P, differ-
ential pressure is measured
as % of full-scale pressure
range using square root
calculation.
k-factor: 0.001 - 9999
TECHNICAL DATA
Supply voltage ...................24 V~/=, ± 15%, 50/60 Hz
Power consumption ........................................... 0.5 W
Output ...............................................0-10 V=, 2-10 V=
Accuracy*
PTH-3202/3203 ........0.5 %×MV*+0.3 %×SR*+2.5 Pa
PTH-3502..................0.5 %×MV*+0.3 %×SR*+5.0 Pa
Maximum pressure
PTH-3202/3203/3502 .......................................30 kPa
Maximum load
0 – 10 V= ...........................................................>2.5kΩ
0 – 20 mA ........................................................ <=450Ω
Dampening (selectable) ............................0.4 s or 10 s
Housing dimensions (h×w×d) ...............91×75×38mm
Cable dimension ..........................................ø3-10 mm
Connection
PTH-3202/3203/3502 ........................ 4 x Screw term,
Pressure tubes .........................................2 × ø6,2 mm
Environment data
Storage temperature ........................... -40°C to +70°C
Operating temperature -20°C to +40°C (continuous)**
0-20 mA, 4-20 mA Operating humidity ...................... 10%RH to 95%RH,
Operating altitude ........................................... ≤2000m
Enclosure rating .....................................................IP54
Weight ..................................................................110 g
*Note: MV = Measured Value / SR = Set measuring
range
**Note: Ambient temperature affects the LCD display
speed and contrast
***Note: DC Supply is recommended if the operation
temperature exceed 40°C
INSTALLATION
PTH must be securely mounted on a level surface
max 1.5mm² using screws. PTH is insensitive to mounting
orientation. However, in order to maintain the
specified enclosure rating, tubes should be at-
tached to both tube connectors if the connectors
point upwards. The enclosure is equipped with
screw holes, see fig. 1.
Pressure is connected by means of tubes. The
non-condensing higher pressure must be connected to the "+"
connector and the lower pressure to the "-"
connector. If the tubes are unintentionally ex-
changed, or the pressure is outside the meas-
urement range, the display flashes. The pressure
tubes must be as short as possible and must
be secured in position to prevent vibration. To
obtain the best possible results, pressure must be
measured where there is least risk of turbulent air
flow, i.e. in the centre of the ventilation duct and
at a suitable distance from bends and branches.
See fig. 2.
The enclosure is opened without the use of tools
by pressing the snap lock at the side of the
connectors. The transmitter cable may be up to
50 m in length and must be connected as shown
in fig. 3.
The transmitter cable must be kept separate from
mains-carrying cables as voltage signals from
these may affect transmitter function.
SETTINGS
Select pressure or flow by setting the DIP switch
(SW1, DIP3) (see figs 3 and 4). To display the
measurement range, press the "" , "" or "OK"
button on the rear cover once (see fig. 5). If the
buttons are not pressed again within 60 seconds,
the display will revert to showing the actual
measured value. Press "" or "" repeatedly
to change the measurement range up/down. The
measurement range will flash on the display until
the setting has been saved by pressing the "OK"
button.
Pressure measurement (fig. 10): If the DIP switch
(SW1, DIP3) is set for pressure measurement,
actual pressure will be shown on the display. Dial
SW2 is not used.
Flow measurement (fig. 11): If the DIP switch
(SW1, DIP3) (fig. 4) is set for flow measurement,
pressing the "OK" button allows the first digit of
the k-factor to be set. The value will flash and can
be set using the "" and "" buttons. When set
0-20 mA, 4-20 mA correctly, press "OK" and set the second, third
and fourth digits correspondingly. Then press
"OK" to save the k-factor and the display will
automatically begin showing the actual measured
value. If standard flow measurement is selected,
no pressure range need be set. An example of
flow calculation is shown in fig. 12.
Square root output (fig. 13): If flow range P is
selected, PTH functions as a pressure transmitter
max 1.5mm²
-30°C to +70°C (short-term)***
non-condensing
© 2021 OJ Electronics A/S
with square root output and flow is displayed in
per cent (Delta P [%]). Full-scale is determined
by the set pressure range (p-range) and the val-
ue shown on the display is calculated as Delta
P [%] = 100x√(Δp/p-range). When flow range P
is selected, pressing "OK" allows the pressure
range to be selected. Once the pressure range
has been selected, press "OK" to save the
setting and the display will automatically begin
showing the actual measured value.
Changing measurement unit: Depending on the
k-factor unit and the selected flow range, attach
one of the accompanying self-adhesive unit
labels to the front cover of the transmitter (see
figs 6 and 7).
Screw terminal 2 of the pressure transmitter can
provide a 0/2 - 10 V output signal while screw
terminal 4 can provide a 0/4 - 20 mA output
signal (see fig. 3).
The minimum value of the output signal is set
on SW1, DIP1 (see fig. 8).
Set the damping time with the DIP switch
(SW1, DIP2) (see figs. 3 and 9). The transmitter
measures the pressure several times within the
set time and the average of these measure-
ments is continuously reproduced in the output
signal. This allows any pressure fluctuations
within the ventilation system to be dampened in
the transmitter output signal.
ZEROING
If necessary, the transmitter can be zeroed
after it has been mounted and the power
supply connected. For best results, wait until
the transmitter has reached usual operating
temperature. Before zeroing the transmitter, it is
important to ensure that the pressure on the "+"
and "-" connectors is equal (e.g. by stopping
the ventilation system). If the display shows a
differential pressure of more than 10 Pa there
may be unintended pressure in the system
(draughts or pinched tubes). It is recommended
that pressure tubes be removed from the "+"
and "-" connectors during zeroing. Zeroing is
activated by pressing the integrated "Zero-set
switch" (SW3) (see fig. 3), after which the yellow
LED will continue to flash until zeroing has been
completed.
LED INDICATION
The green LED is lit when the power supply
has been connected correctly. The yellow LED
flashes for approx. 3 seconds during zeroing.
LED ON Flashing
Green OK
Zeroing in
Yellow
progress
FIGURES
Fig. 1: Dimensioned sketch
Fig. 2: Transmitter position in relation to
bends and branches
Fig. 3: Wiring diagram
Fig. 4: Pressure/flow selection
Fig. 5: Measurement range selection
Fig. 6: Measurement unit indication
Fig. 7: Measurement unit label selection
Fig. 8: Output signal selection
Fig. 9: Damping time selection
Fig. 10: Pressure settings
Fig. 11: Flow settings
Fig. 12: Flow calculation example
Fig. 13 Square root settings
Fig. 14: Orientation of PTH
Product disposal
Products marked with this symbol
must not be disposed of along with
household refuse but must be
Off
No power
OK
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