HK Instruments DPT-MOD Series User manual

Copyright HK Instruments 2014 www.hkinstruments. Installation version 2.0 2014
INSTALLATION
INSTRUCTIONS
DIFFERENTIAL PRESSURE TRANSMITTERS
DPT-MOD Series
WARNING
• READ THESE INSTRUCTIONS CAREFULLY BEFORE
ATTEMPTING TO INSTALL, OPERATE OR SERVICE THIS
DEVICE.
• Failure to observe safety information and comply with
instructions 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 with
insulation rated for full device operating voltage.
• To avoid potential fire and/or explosion do not use in potentially
flammable 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 the
installation will be functional and safe. Use only experienced
and knowledgeable technicians to install this device.
SPECIFICATIONS
INTRODUCTION
Thank you for choosing an HK Instruments DPT-MOD series dif-
ferential pressure transmitter. The DPT-MOD differential pressure
transmitter for air conforms to Modbus over serial line protocol,
using RTU transmission mode and RS485 interface. The digital
output signal is sent over Modbus enabling the DPT-MOD to con-
nect directly to a field communications network.
DPT-MOD requires less wiring than traditional 3-wire transmitters,
since multiple devices can be connected on serial line.
The DPT-MOD includes an Input terminal that enables reading of
multiple other signals such as temperature or control relays over
Modbus. The Input terminal has two input channels designed to
accept 0−10 V, ntc10k, Pt1000, Ni1000/(-LG), and BIN IN (poten-
tial free contact) signals. For example, DPT-MOD can read values
from one differential pressure measurement point and two tem-
perature measurement points.
APPLICATIONS
DPT-MOD series devices are commonly used in HVAC/R
systems for:
• fan, blower and filter monitoring
• pressure and flow monitoring
• valve and damper control
• pressure monitoring in cleanrooms
SPECIFICATIONS
Performance
Accuracy (from applied pressure):
±1.5 % + 1 Pa
(Including: general accuracy, temperature drift, linearity,
hysteresis, long term stability and repetition error)
Response time:
1...20 s selectable via menu
Max pressure:
400 kPa
Communication
Protocol: MODBUS over Serial Line
Transmission Mode: RTU
Interface: RS485
Byte format (11 bits) in RTU mode:
Coding System: 8-bit binary
Bits per Byte:
1 start bit
8 data bits, least significant bit sent first
1 bit for parity
1 stop bit
Baud rate: selectable in configuration
Modbus address: 1−247 addresses selectable in
configuration menu
Zero point calibration options:
• Manual pushbutton autozero
• Via Modbus write coil
Technical Specifications
Media compatibility:
Dry air or non-aggressive gases
Measuring units:
Selectable via menu (Pa, mbar, inchWC, mmWC, psi)
Measuring element:
Piezoresistive
Environment:
Operating temperature: -10...+50 °C
Storage temperature: -20...+70 °C
Humidity: 0 to 95 % rH
Physical
Dimensions:
Case: 102.0 x 71.5 x 36.0 mm
Weight:
150 g, with accessories 290 g
Mounting:
2 each 4.3 mm screw holes, one slotted
Materials:
Case: ABS
Lid: PC
Pressure inlets: Brass
Duct connectors: ABS
Tubing: PVC
Protection standard:
IP54
Display:
2-line display (12 characters/line)
Line 1: active measurement
Line 2: units
Electrical Connections:
4+3 spring load terminals, max 1.5 mm2
Cable Entry: M20
Pressure fittings:
Male 5,0 mm and 6,3 mm
Electrical
Supply voltage:
24 VAC or VDC ± 10 %
Power consumption:
< 1.3 W
Output signal:
via Modbus
Conformance
Meets requirements for CE marking:
EMC directive 2004/108/EC
RoHS Directive 2002/95/EC

Copyright HK Instruments 2014 www.hkinstruments. Installation version 2.0 2014
SCHEMATICS
DIMENSIONAL DRAWINGS
INSTALLATION
Figure 1a - Surface mounting
STEP 1: MOUNTING THE DEVICE
1) Mount the device in the desired location (see step 1).
2) Open the lid and route the cable through the strain relief and
connect the wires to the terminal block(s) (see step 2).
3) The device is now ready for configuration.
WARNING! Apply power only after the device is properly
wired.
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.
Figure 1b - Mounting orientation
Figure 1c - Application connections
DPT
DPT
Display connection
A
B
24 V
GND
LEDs
Joystick 1
Joystick 2
Joystick 3
Select
Up
Down
Menu buttons
Terminal
blocks
Pressure
sensor
Input terminal
configuration
jumpers
Input 1
Input 2
GND
GND
InputOutput
YES NO NO
Static pressure Filter/Damper
monitoring
Fan/Blower
monitoring
Not
connected

Copyright HK Instruments 2014 www.hkinstruments. Installation version 2.0 2014
STEP 2: WIRING DIAGRAMS CONFIGURATION CONTINUED
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.
Figure 2a - Wiring diagram
Figure 2b - Wiring diagram example for input signals
NOTE! Supply voltage must be connected one hour before the
zero point adjustment is carried out. Access via Modbus or by
push button.
1) Loose both tubes from the pressure inlets + and -.
2) Press the select button briefly.
3) Wait until the LED turns off and then install tubes again for
the pressure inlets.
STEP 3: CONFIGURATION
Input 1
Input 2
GND
GND
Pt1000
NTC10k
J1
J2
J3
IN1 IN2
Input 1 Pt1000 temperature:
Function 04 - Read input register 3x0005
Input 2 NTC10k temperature:
Function 04 - Read input register 3x0008
1) Activate the device Menu by pushing the the select button for 2
seconds.
2) Select the address for Modbus: 1...247
BAUD RATE
9600
SELECT
UP
DOWN
ADDRESS
99
SELECT
UP
DOWN
PARITY BIT
NONE
SELECT
UP
DOWN
3) Select the baud rate: 9600/19200/38400.
4) Select the parity bit: None/Even/Odd
5) Select the pressure unit for display: Pa/inchWC/mmWC/psi/mbar
PRESS. UNIT
Pa
SELECT
UP
DOWN
6) Select the response time: 1...20 s
RESPONSETIME
20 s
SELECT
UP
DOWN
7) Push the select button to exit menu.
SELECT
EXIT MENU SELECT
STEP 4: ZERO POINT ADJUSTMENT
SELECT
STEP 5: INPUT SIGNAL CONFIGURATION
Input signals can be read over Modbus via DPT MOD RS485
interface.
Signals Accuracy for measurement Resolution
0...10 V < 0,5 % 0,1 %
NTC10k < 0,5 % 0,1 %
Pt1000 < 0,5 % 0,1 %
Ni1000/(-LG) < 0,5 % 0,1 %
BIN IN (potential free contact)
The jumpers should be set according to the instructions below and
the value should be read from the right register. Both inputs can be
configured independently.
Figure 3 - Input signal configuration
J1
J2
J3
IN1 IN2
J1
J1
J1
J2
J2
J2
J3
J3
J3
NTC10k / BIN IN
Pt1000 / Ni1000(-LG)
0...10 V
A
B
24 V
GND
+ Power Supply
24VDC / 24VAC
Input 1
Input 2
GND
GND

Copyright HK Instruments 2014 www.hkinstruments. Installation version 2.0 2014
STEP 6: MODBUS REGISTERS WARRANTY POLICY
The seller is obligated to provide a warranty of 24 months for the de-
livered goods regarding material and manufacturing. The warranty
period is considered to start on the delivery date of the product. If
a defect in raw materials or a production flaw is found, the seller is
obligated, when the product is sent to the seller without delay or be-
fore expiration of the warranty, to amend the mistake at his/her dis-
cretion either by repairing the defective product or by delivering free
of charge to the buyer 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 com-
prise 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 re-
construction, or changes and installation work not done by the seller
or his/her authorized representative. The selection of materials for de-
vices prone to corrosion is the buyer’s responsibility, unless otherwise
is legally agreed upon. Should the manufacturer alter the structure of
the device, the seller is not obligated to make comparable changes to
devices already purchased. Appealing for warranty requires that the
buyer has correctly fulfilled his/her duties arisen from the delivery and
stated in the contract. The seller will give a 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 or device, or if needed, a new
part or device, but not installation or exchange costs. Under no cir-
cumstance is the seller liable for damages compensation for indirect
damage.
Register Parameter description Data Type Value Range
3x0001 Program version 16 bit 0...1000 0,00...99,00
3x0002 Pressure reading 16 bit -250...2500/7000 -250...2500/7000 (Pa)
3x0004 Input 1: 0...10 V 16 bit 0...1000 0...100 %
3x0005 Input 1: Pt1000 16 bit -500...500 -50...+50 °C
3x0006 Input 1: Ni1000 16 bit -500...500 -50...+50 °C
3x0007 Input 1: Ni1000-LG 16 bit -500...500 -50...+50 °C
3x0008 Input 1: NTC10k 16 bit -500...500 -50...+50 °C
3x0009 Input 2: 0...10 V 16 bit 0...1000 0...100 %
3x0010 Input 2: Pt1000 16 bit -500...500 -50...+50 °C
3 x 0 011 Input 2: Ni1000 16 bit -500...500 -50...+50 °C
3x0012 Input 2: Ni1000-LG 16 bit -500...500 -50...+50 °C
3x0013 Input 2: NTC10k 16 bit -500...500 -50...+50 °C
Function 04 - Read input register
Function code 02 - Read input status
Register Parameter description Data Type Value Range
1x0001 Input 1: BIN IN Bit 0 0...1 On - Off
1x0002 Input 2: BIN IN Bit 0 0...1 On - Off
Function 05 - Write single coil
Register Parameter description Data Type Value Range
0x0001 Zeroing function Bit 0 0...1 On - Off
Function code 06 - Write single register
Register Parameter description Data Type Value Range
4x0001 Beta value of NTC thermistor 16 bit 0...30000 1...30000 (Default: 4220)