DIFFERENTIAL PRESSURE TRANSMITTERS
DPT-R8 Series
INTRODUCTIONINSTALLATIONINSTRUCTIONSWARNING

Thank you for choosing an HK Instruments DPT series differential
pressure transmitter. The DPT series is intended for use in commercial environments. It is designed with six unit selections (Pa, kPa,mbar, inchWC, mmWC, psi) and eight field selectable measurement
ranges (unidirectional and bi-directional) to meet your application
requirements. The DPT-R8 series is comprised of the DPT250-R8with ranges from 25 Pa to 250 Pa, the DPT2500-R8 with ranges
from 100 Pa to 2500 Pa, and the DPT7000-R8 with ranges from1000 Pa to 7000 Pa.
All DPT-R8 series differential pressure transmitters are available
with display and autozero calibration.

• READ THESE INSTRUCTIONS CAREFULLY BEFOREATTEMPTING TO INSTALL, OPERATE OR SERVICE THIS
DEVICE.
• Failure to observe safety information and comply withinstructions can result in PERSONAL INJURY, DEATH AND/OR
PROPERTY DAMAGE.
• To avoid electrical shock or damage to equipment, disconnect
power before installing or servicing and use only wiring withinsulation rated for full device operating voltage.
• To avoid potential fire and/or explosion do not use in potentiallyflammable or explosive atmospheres.
• Retain these instructions for future reference.
• This product, when installed, will be part of an engineered
system whose specifications and performance characteristics
are not designed or controlled by HK Instruments. Review
applications and national and local codes to assure that theinstallation will be functional and safe. Use only experienced andknowledgeable technicians to install this device.

APPLICATIONSDPT-R8 series devices are commonly used in HVAC/R systems for:• fan, blower and filter monitoring• pressure and flow monitoring• valve and damper control
SPECIFICATIONS• pressure monitoring in cleanrooms

SPECIFICATIONS
Performance

Accuracy (from applied pressure):
Models 250 and 2500:     Pressure < 125 Pa = 1 % + ±2 Pa     Pressure > 125 Pa = 1 % + ±1 Pa
Model 7000:     Pressure < 125 Pa = 1.5 % + ±2 Pa     Pressure > 125 Pa = 1.5 % + ±1 Pa(including: general accuracy, linearity, hysteresis, longterm stability, and repetition error)
Thermal effects:
Temperature compensated 0...50 °C
Overpressure:
Proof pressure: 25 kPa
Burst pressure: 30 kPa
Zero point calibration:
Automatic autozero or manual pushbutton
Response time:
8.0 s or 0.8 s, selectable via jumper

Technical Specifications

Media compatibility:
Dry air or non-aggressive gases
Measuring units:Pa, kPa, mbar, inchWC, mmWC, psi, selectable via
jumperMeasuring element:
MEMS, no flow-throughCopyright HK Instruments 2018

Environment:
Operating temperature: -20...50 °C,-40C model: -40...50  °C
AZ-model: -20...50 °C,  
Models with autozero calibration: -5...50 °C
Storage temperature: -40...70 °C,-40C model: -40...70 °C
Humidity: 0 to 95 % rH, non condensing

PhysicalDimensions:Case: 90.0 x 95.0 x 36.0 mm
Weight:
150 g
Mounting:
2 each 4.3 mm screw holes, one slotted
Materials:
Case: ABS
Lid: PC
Duct connectors: ABS
Tubing: PVC
Protection standard:
IP54
Display (Optional)
2-line display (12 characters/line)
Line 1: active measurement
Line 2: units
Electrical connections:4-screw terminal block
Wire: 0.2–1.5 mm2  (12–24 AWG)
Cable entry: M16
Pressure fittings:
Male ø 5,0 mm and 6,3 mm

www.hkinstruments.fi+ High pressure− Low pressure

ElectricalVoltage:
Circuit: 3-wire (V Out, 24 V, GND)
Input: 24 VAC or VDC, ±10 %Output: 0–10V
Power consumption: <1.0 W,-40C model: <4.0 W when <0 °C
Resistance minimum: 1 kΩCurrent:
Circuit: 3-wire (mA Out, 24 V, GND)
Input: 24 VAC or VDC, ±10 %Output: 4–20 mA
Power consumption: <1.2 W,-40C model: <4.2 W when <0 °C
Maximum load: 500 Ω
Minimum load: 20 ΩConformance

Meets the requirements for CE marking:
EMC Directive 2014/30/EU
RoHS Directive 2011/65/EU
WEEE Directive 2012/19/EU

COMPANY WITH
MANAGEMENT SYSTEMCERTIFIED BY DNV GL= ISO 9001 = ISO 14001 =RoHS 2
2011/65/EU

Installation version 6.0 2018

SCHEMATICSSTEP 1: MOUNTING THE DEVICE
1) Select the mounting location (duct, wall, panel).
2) Use the device as a template and mark the screw holes.
3) Mount with appropriate screws.

Pressure sensor

Zero button

Figure 1a - Mounting orientation

Connection for
optional display

LEDJumpers

Terminal block

YESNONO

Figure 1b - Application connections
Static pressure

DIMENSIONAL DRAWINGS

Filter/Damper
monitoring

Fan/Blower
monitoring

Not
connected90.036.0

77.0

For CE compliance, a properly grounded shielding cable is required.
1) Unscrew the strain relief and route the cable(s).
2) Connect the wires as shown in figure 2a and 2b.
3) Tighten the strain relief.

95.0

53.0

71.5

STEP 2: WIRING DIAGRAMS

Figure 2a - Wiring diagram 0–10 V output

4.3

0–10 V
4–20 mAV

INSTALLATION+ Power supply
24 VDC / 24 VAC

1) Mount the device in the desired location (see step 1).
2) Open the lid and route the cable through the strain relief andconnect the wires to the terminal block(s) (see step 2).
3) The device is now ready for configuration.

GNDFigure 2b - Wiring diagram 4–20 mA output

0–10 V  WARNING! Apply power only after the device is properly wired.

4–20 mA
ACopyright HK Instruments 2018

24 V

www.hkinstruments.fi+ Power supply
24 VDC / 24 VAC

24 VGND

Installation version 6.0 2018

STEP 3: CONFIGURATIONSELECTING THE MEASUREMENT RANGE CONTINUED

1) Select the desired measurement unit. (see step 4)2) Select the desired measurement range. (see step 5)3) Select the desired response time. (see step 6)4) Zero the device. (see step 7)5) Connect the pressure tubes. Connect positive pressure toport labeled “+” and negative pressure to port “-”.
6) Close the lid. The device is now ready to be used.

2) Install jumpers on J1, J2 and J3 as required.
a. Using the range number from 1c above, find the corresponding
range number in Chart 2.
b. Install jumpers on J1, J2 and J3 on device, as shown under the range
number in Chart 2. (Grey colour indicates that a jumper is installed.
Reference figure 3 for jumper installation.)
Chart 2

STEP 4: SELECTING THE MEASUREMENT UNIT

Range 1

Range 2Range 3Range 4

Range 5

Range 6Range 7

Range 8Jumper J1

1) To change the measurement unit appearing on the display, install ajumper to both pins of J5 (see Figure 3).
2) Push down the zero button and the measurement unit options (Pa,kPa, mbar, inchWC, mmWC, psi) will cycle on the display.
3) To select a unit option to display, remove the jumper from J5
while the measurement unit is visible on the display.

Jumper J2
Jumper J3(Grey colour indicates that a jumper is installed. Reference Figure 3 and Schematics for jumper installation.)

STEP 6: SELECTING THE RESPONSE TIME
The response time affects how fast the transmitter reacts to changes inthe system. The response time is the time the device takes to reach 63% of the measured value. To smooth out unstable pressure fluctuations
in airflow applications, select a longer response time.

Figure 3 - Jumper installation

No jumper
Circuit open

Jumper installed
Circuit closed

Example:Selected response time: 8.0 seconds
Result: Output signal achieves a new value in 20 seconds (Responsetime*5)Jumper stored(Grey colour indicates that a jumper is installed)

STEP 5: SELECTING THE MEASUREMENT RANGE
1) Determine the range number
a. Find the model in Chart 1.
b. Find the measurment unit (selected in step 4).
c. Find the required measurement range on the same line as the   measurement unit (b above) and determine the range number in theheader.

To change response time, install or remove jumper on J4.
(see Figure 3)
1) Install jumper on J4 for 8.0 second response time.
2) Remove jumper from J4 for 0.8 second response time.

Chart 1Model DPT250-R8
Range 1Range 2Range 3

Range 4

Range 5

Range 6

Range 7

Range 8

Pa

0–25

0–50

0–100

0–250

-25–25-50–50-100–100-150–150kPa

0–0.025

0–0.05

0–0.1

0–0.25-0.025–0.025 -0.05–0.05-0.1–0.1-0.15–0.15

mbar

0–0.25

0–0.500–1.000–2.50-0.25–0.25-0.50–0.50-1.0–1.00-1.50–1.50

inchWC

0–0.100–0.200–0.400–1.00-0.10–0.10-0.20–0.20-0.40–0.40-0.60–0.60

mmWC

0–2.6

0–5.1

0–10.2

0–25.5-2.6–2.6-5.1–5.1-10.2–10.2-15.3–15.3

0–0.0036

0–0.0073

0–0.0145

0–0.0363 -0.0036–0.0036 -0.0073–0.0073 -0.0145–0.0145 -0.0036–0.0036

psi

Model DPT2500-R8
Range 1

Range 2Range 3Range 4

Range 5

Range 6

Range 7

Range 8

Pa-100–100

0–100

0–250

0–500

0–10000–15000–2000

0–2500kPa-0.10–0.10

0–0.100–0.25

0–0.500–1.000–1.500–2.000–2.50mbar-1.00–1.00

0–1.000–2.500–5.000–10.00–15.00–20.0

0–25.00–10.00

inchWC-0.40–0.40

0–0.400–1.000–2.00

0–4.00

0–6.000–8.00mmWC-10.2–10.2

0–10.2

0–25.5

0–51.00–102.0

0–153.0

0–204.0

0–255.0

psi-0.0145–0.0145

0–0.0145

0–0.0363

0–0.0725

0–0.1450

0–0.21725

0–0.2900

0–0.3625

Model DPT7000-R8

Copyright HK Instruments 2018

Range 1

Range 2Range 3Range 4

Range 5

Range 6

Range 7

Range 8Pa

0–10000–15000–2000

0–25000–30000–40000–50000–7000kPa

0–1.000–1.500–2.0

0–2.500–3.00

0–4.000–5.000–7.00mbar

0–10.00–15.00–20.00–25.00–30.00–40.00–50.00–70.0inchWC

0–4.00

0–6.000–8.000–10.00–12.00

0–16.00

0–20.00

0–28.00mmWC

0–102.0

0–153.0

0–204.0

0–255.0

0–306.00–408.00–510.0

0–714.0

psi

0–0.1450

0–0.21725

0–0.2900

0–0.3625

0–0.4350

0–0.5800

0–0.7250

0–1.0150

www.hkinstruments.fi

Installation version 6.0 2018

STEP 7: ZEROING THE DEVICE-40C MODEL: OPERATION IN COLD ENVIRONMENTNOTE! Always zero the device before use.

The lid of the device has to be closed when the operation temperature
is below 0 °C. The display needs 15 minutes to warm up if the device
is started in temperature below 0 °C.

To zero the device two options are available:
1) Manual Pushbutton zero point calibration
2) Autozero calibration

NOTE! The power consumption rises when the operation temperature
is below 0 °C.

Does my transmitter have an autozero calibration? See the product label. If it shows -AZ in the model number, then you have the autozero
calibration.
1) Manual Pushbutton zero point calibration
NOTE: Supply voltage must be connected at least one hour prior to zero
point adjustment.
a) Disconnect both pressure tubes from the pressure ports labeled +a) Disconnect both pressure tubes from the pressure ports labeled +and –.
and –.
b) Push down the zero button (joystick) until the LED light (red)b) Push down the zero button until the LED light (red) turns on and theturns on and the display reads “zeroing” (display option only). (seedisplay reads “zeroing” (display option only). (see Figure 4)
Figure 6)c) The zeroing of the device will proceed automatically. Zeroing isc) The zeroing of the device will proceed automatically. Zeroing iscomplete when the LED turns off, and the display reads 0 (display
complete when the LED turns oﬀ, and the display reads 0 (display
option only).
option only).
d) Reinstall the pressure tubes ensuring that the High pressure tubed) Reinstall the pressure tubes, ensuring the High pressure tube is
is connected to the port labeled +, and the Low pressure tube isconnected to the port labeled +, and the Low pressure tube isconnected to the port labeled −.
connected to the port labeled −.
Figure 4
Press down button
LED turns ON
Display reads “Zeroing”
LED2) Autozero calibration
If the device includes the optional autozero circuit, no action is required.
Autozero calibration (-AZ) is an autozero function in the form of an
automatic zeroing circuit built into the PCB board. The autozero calibration electronically adjusts the transmitter zero at predetermined
time intervals (every 10 minutes). The function eliminates all output
signal drift due to thermal, electronic or mechanical effects, as well as
the need for technicians to remove high and low pressure tubes when
performing initial or periodic transmitter zero point calibration. The
autozero adjustment takes 4 seconds after which the device returns to
its normal measuring mode. During the 4 second adjustment period,
the output and display values will freeze to the latest measured value.

RECYCLING/DISPOSAL
The parts left over from installation should berecycled according to your local instructions.
Decommissioned devices should be taken to a
recycling site that specializes in electronic waste.

WARRANTY POLICY
The seller is obligated to provide a warranty of five years for the delivered goods regarding material and manufacturing. The warranty period
is considered to start on the delivery date of the product. If a defectin raw materials or a production flaw is found, the seller is obligated,when the product is sent to the seller without delay or before expiration of the warranty, to amend the mistake at his/her discretion either
by repairing the defective product or by delivering free of charge to thebuyer a new flawless product and sending it to the buyer. Delivery costs
for the repair under warranty will be paid by the buyer and the return
costs by the seller. The warranty does not comprise damages caused by
accident, lightning, flood or other natural phenomenon, normal wear
and tear, improper or careless handling, abnormal use, overloading, improper storage, incorrect care or reconstruction, or changes and installation work not done by the seller or his/her authorized representative.
The selection of materials for devices prone to corrosion is the buyer’sresponsibility, unless otherwise is legally agreed upon. Should the manufacturer alter the structure of the device, the seller is not obligated tomake comparable changes to devices already purchased. Appealing forwarranty requires that the buyer has correctly fulfilled his/her duties
arisen from the delivery and stated in the contract. The seller will givea new warranty for goods that have been replaced or repaired within
the warranty, however only to the expiration of the original product’s
warranty time. The warranty includes the repair of a defective part ordevice, or if needed, a new part or device, but not installation or exchange costs. Under no circumstance is the seller liable for damages
compensation for indirect damage.

Transmitters equipped with the autozero calibration are virtually
maintenance free.

Copyright HK Instruments 2018www.hkinstruments.fi

Installation version 6.0 2018