OJ Electronics PTH-3202 Instructions

INSTRUCTIONS
Type PTH-3202
English
PTH is a series of electronic pressure
transmitters designed primarily to measure
total and differential air pressures in ventilation
systems. The resulting measurements are used
for monitoring, control and regulation purposes
via a regulator, PLC or monitoring system.
Typical applications include:
- The maintenance/control of constant pressure
at a given position within the duct system.
- The maintenance/control of desired
underpressure within the duct system.
- The measurement of pressure differentials
across filters to determine optimum filter
replacement time.
- Flow determination via differential pressure
measurements across a standard aperture.
PRODUCT PROGRAMME
Type Product
PTH-3202 Pressure transmitter,
0-2500 Pa, 1 channel, IP54
FUNCTION
PTH is a pressure transmitter for comfort
ventilation systems. It provides an active current
or voltage signal proportional to the measured
air pressure. PTH consists of semiconductor
elements. There is no air throughput and
the unit is thus protected against dust in the
ventilation system. The pressure element is
temperature compensated to provide accurate
pressure measurement throughout the specified
temperature range.
The required measuring range of the pressure
transmitter is set with DIP switches. The output
signal can be changed from voltage [V] to current
[mA] by setting a jumper. A DIP switch allows
two different damping times to be selected so
that pressure fluctuations within the ventilation
system are attenuated in the transmitter output
signal. A green LED indicates that supply voltage
has been connected correctly. If the actual
pressure is outside the selected measuring
range, the green LED flashes.
CE MARKING
OJ Electronics A/S hereby declares that the
product is manufactured in accordance with
Council Directive 92/31/EEC on electromagnetic
compatibility (and subsequent amendments)
and Council Directive 73/23/EEC on electrical
equipment designed for use within certain
voltage limits.
Applied standards
EN 61000-6-2 and EN 61000-6-3
Electromagnetic compatibility (EMC)
TECHNICAL DATA
Supply voltage ...................24 V~/=, ± 15%, 50/60 Hz
Power consumption ........................................... 0.5 W
Output ...............................................0-10 V=, 2-10 V=
0-20 mA, 4-20 mA
Measuring range Pressure ......PTH-3202 / 0-2500 Pa
Pressure ranges ......................... PTH-3202 (see fig. 5)
Accuracy*
PTH-3202..................1.5 %×MV*+0.3 %×SR*+2.5 Pa
Maximum pressure PTH-3202
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
Pressure tubes .........................................2 × ø6,2 mm
Environment data
Operating temperature -20°C to +40°C (continuous)
Operating humidity ...................... 10%RH to 95%RH,
Operating altitude ........................................... ≤2000m
Enclosure rating .....................................................IP54
Weight ..................................................................110 g
*Note: MV = Measured Value / SR = Set
measuring range
MOUNTING
PTH must be securely mounted on a level surface
using screws. PTH is insensitive to mounting
orientation. However, in order to maintain the
specified enclosure, tubes should be attached 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 higher pressure must be connected to the "+
connector" and the lower pressure to the
"- connector". If the tubes are unintentionally
exchanged, or the pressure is outside the
measuring range, the green LED flashes. See
table 1. 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 turbulence, 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
Pressure range is set by turning the dial, SW2
(see fig. 3)
With PTH-3202, pressure range can be set in
intervals ranging from -50/+50 Pa to 0-2500 Pa
(see fig. 5).
If the dial is set to values other than the
specified positions (0-7), the pressure
transmitter will interpret the setting as position 7
corresponding to the highest pressure range. If
the pressure transmitter is inadvertently set to a
pressure range lower than the pressure
encountered in the connectors, the green LED
will light constantly (see table 1).
The screw terminals of the pressure transmitter
can provide a 0/2 - 10 V output signal and/or a
0/4 - 20 mA output signal (see fig. 4).
The 0-10 V output signal is provided by terminal
2 with DIP 1 of SW1 in position "Off".
The 2-10 V output signal is provided by terminal
2 with DIP 1 of SW1 in position "On".
The 0-20 mA output signal is provided by
terminal 4 with DIP 1 of SW1 in position "Off".
The 4-20 mA output signal is provided by
terminal 4 with DIP 1 of SW1 in position "On"
(see figs 4 & 7).
Output signal damping time can be set to 0.4 s
............... kPa or 10 s using DIP2 of SW1 (see figs 3 & 8). The
transmitter measures the pressure several
..........4 x Screw term, max 1.5mm²
non-condensing
times within the set time and the output signal
consists of the average of these measurements.
This allows any pressure fluctuations within
the ventilation system to be dampened in the
transmitter output signal.
ZEROING
The transmitter can be zeroed after it has been
mounted and the power supply connected.
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 yellow LED is
constantly lit, the transmitter is measuring a
differential pressure of more than 50 Pa. This
may be caused by unintended pressure within
the system (draughts or compressed tubing). It
is recommended that tubes be removed from
the + and - connectors during zeroing. Zeroing
is activated by pressing the integrated zero-set
switch (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 and flashes when the
actual pressure is above or below the selected
measuring range. The yellow LED is lit if
pressure exceeds 50 Pa and flashes for approx.
3 seconds during zeroing.
Table 1
LED on On Flashing
Green OK Pressure outside
set range
Yellow >50Pa Zeroing in progress
FIGURES
Fig. 1: Dimensioned sketch
Fig. 2: Transmitter position in relation to bends
and branches
Fig. 3: PCB component positions
Fig. 4: Wiring diagram
Fig. 5: Selection of pressure range: PTH-3202
Fig. 7: Selection of output voltage/current
Fig. 8: Selection of damping time
Fig. 9: Free DIP switch
Product disposal
Products marked with this symbol
must not be disposed of along with
household refuse but must be
delivered to a waste collection centre
in accordance with current localregula-
tions.
Disclaimer
OJ cannot be held liable for any errors in cata-
logues, brochures or other printed material. OJ
reserves the right to alter its products without
notice. This also applies to products already
on order, provided that such alterations can be
made without requiring subsequent changes in
specifications already agreed. All trademarks in
this material are the property of the respective
companies. OJ and the OJ logotype are trade-
marks of OJ Electronics A/S. All rights reserved.
OJ ELECTRONICS A/S
Stenager 13B · DK-6400 Sønderborg
Tel: +45 73 12 13 14 · Fax: +45 73 12 13 13
oj@ojelectronics.com · www.ojelectronics.com
Off
No
supply
<50Pa