HDI 2021 User manual

Houston Digital Instruments, Inc. 7240 BRITTMOORE RD ● Houston, TX 77041 Ph 713-688-8555 Fx 713-688-2228
HDI 2021 4-20mA
Transmitter
(Custom designed top pictured above. Unit may vary)
Operation and
Maintenance Manual
Revision: 3

Houston Digital Instruments, Inc. ● 7240 BRITTMOORE RD ● Houston, TX 77092 Ph 713-688-8555 Fx 713-688-2228
Revision: 3 - 2 -
SECTION I
Systems General Information:
A. General Information....................................................................................................1
B. Unpacking and Inspection
C. Precautionary Information
D. Personnel Qualifications
SECTION II
System Description:
A. Systems Description....................................................................................................2.A
B. System Components
2.B.1. Pressure Transducers..............................................................................2.B.1
2.B.2 Cables.....................................................................................................2.B.2
C. System Capacities.......................................................................................................2.C
2.C.1. Transducers.............................................................................................2.C.1
SECTION III
Installation:
A. Components
3.A.1. Transducers ............................................................................................3.A.1
3.A.2. Cables.....................................................................................................3.A.2
B. Mounting Components
3.B.1. Pressure Transducers..............................................................................3.B.1
SECTION IV
Theory of Operation:
A. Pressure System ..........................................................................................................4.A
B. Factory Preset Calibration...........................................................................................4.B
SECTION V
Maintenance:
A. Guidelines ...................................................................................................................5.A
B. Schematic Drawing / Parts List ..................................................................................5.B
SECTION VI
Certifications:
A.CSA certificate and Tag................................................................................................6.A
B. ATEX certificate and Tag ...........................................................................................6.B

Houston Digital Instruments, Inc. ● 7240 BRITTMOORE RD ● Houston, TX 77092 Ph 713-688-8555 Fx 713-688-2228
Revision: 3 - 3 -
SECTION VII
Warranty:

Houston Digital Instruments, Inc. ● 7240 BRITTMOORE RD ● Houston, TX 77092 Ph 713-688-8555 Fx 713-688-2228
Revision: 3 - 4 -
SECTION I
General Information
A General Information:
This manual describes the installation, operation, maintenance and calibration of the HDI
2021 Transducer Assembly. This manual will provide the user with information necessary to
properly utilize the instrument. Included in this manual are all the necessary procedures to
install and maintain this instrument properly.
B Unpacking and Inspection:
Upon receipt account for all pieces on the packing list. If any items are missing, immediately
inform the freight forwarder. Inspect all items for damage. If any items are damaged,
immediately inform the freight forwarder and Houston Digital Instruments, Inc.
C Precautionary Information:
Assure all directions on the packages are followed during unpacking and handling. Extra care
should be taken to assure that the pressure sensor, which is mounted in the transducer housing
supplied with the system, is protected from contact with any hard or sharp objects, i.e.
screwdriver, fingernail, etc., during the installation of the sensor. Any evidence of
mishandling or abuse shall VOID the warranty. (See Section VI Warranty for detailed
coverage) Also avoid any extreme tightening efforts, with a hammer, at installation.
D Personnel Qualifications:
This equipment requires experienced personnel to handle, install and maintain. HDI may
provide technical schooling if required at their Houston facility or on-site.
SECTION II
Systems Description:
A Systems Description:
The transducer (sensor) is an embedded strain gauge housed in a stainless steel case. The
strain gauge is commonly housed in either a 1502 hammer union or a flange. Any style
housing may be specified by the customer.
B Systems Components:
2.B.1 Pressure Transducer: 2” 1502, 2” 2202, 1” NPT transducer housing or
possible Flanged housings:

Houston Digital Instruments, Inc. ● 7240 BRITTMOORE RD ● Houston, TX 77092 Ph 713-688-8555 Fx 713-688-2228
Revision: 3 - 5 -
2.B.2 Cables:
A high grade shipboard approved instrument cable with woven shield is recommended to
reduce noise interference. Other types of cable are available at additional cost.
C System Capacities:
2.C.1 Transducer:
Transducers are rated at full range. Units 10K and under are capable of withstanding a 30
percent over pressurization without damage to the system. 16K units are capable of
withstanding a 10 percent over pressurization without damage to the system. System
capacities are as follows:
6,000 PSI 10,000 PSI 16,000 PSI 20,000 PSI* (Developmental)
SECTION III
Installation:
3.A Components:
3.A.1 Transducer:
The transducer is to be mounted by the customer at the locations deemed most suitable for
such equipment.
3.A.2 Cables:
Maximum recommended cable length is 200'. Cable lengths, other than standard, shall have
been specified by the customer to the factory in advance. Other cable types are available upon
request. Cabling will be installed using acceptable industry standards for such installations.
3.B Mounting Components:
3.B.1 Pressure Transducer:
The pressure system transducer comes from the factory as a complete assembly and only
requires mounting of the transducer housing using standard practices for such installations.
Note: Special care should be taken to insure that the transducer pill mounted in the center of
the transducer housing, is not allowed to make contact with any hard and/or sharp object as
the accuracy and the sensitivity could be affected. The transducer pill is vulnerable to this
type of contact. Any evidence of mishandling or abuse shall void the warranty. We have

Houston Digital Instruments, Inc. ● 7240 BRITTMOORE RD ● Houston, TX 77092 Ph 713-688-8555 Fx 713-688-2228
Revision: 3 - 6 -
installed an “orifice plate” to help minimize direct contact; in doing so, regular cleaning
should be performed to increase longevity with the above precautions.
SECTION IV
Theory of Operation:
4.A Pressure System:
The major components of this system are the transducer and the communications link (cable).
The transducer utilizes a four active arm Wheatstone Bridge Strain Gauge which, when
excited by the current source, will produce an electrical signal that is proportional to pressure
applied to it. The cabling serves as an interconnect for the transducer, taking the excitation
power in and carrying away the signal.
4.B Factory Preset Calibration:
The HDI 2021 is a digital electronic pressure measurement device designed specifically for
Oilfield applications. This system has been factory preset and will not require periodic
calibration as with the previous version of the HDI 2021 or to our similar product line, HDI
2400 Pressure Gauge Systems.
The HDI 2000 is based on a "Strain Gauge" design concept. The calibration of the strain
gauge is similar to tuning a stringed instrument. It is necessary to understand the system is
based on small resonant electronic signals.
The baseline for calibration is the current excitation across the bridge. This is preset at the
factory and cant be changed.
SECTION V
Maintenance:
5.A Guidelines:
First, maintain the integrity of the cable and visually check for abuse. Second, assure the
system is cleaned and checked periodically for damage following our listed precautions. Last
of all, set a schedule for periodic calibrations by Houston Digital Instruments, if required.

Houston Digital Instruments, Inc. ● 7240 BRITTMOORE RD ● Houston, TX 77092 Ph 713-688-8555 Fx 713-688-2228
Revision: 3 - 7 -
5.B Schematic Drawing / Parts List: (pending)

Houston Digital Instruments, Inc. ● 7240 BRITTMOORE RD ● Houston, TX 77092 Ph 713-688-8555 Fx 713-688-2228
Revision: 3 - 8 -
SECTION VI
Certification:
6.A CSA Certificate and
Tag:

Houston Digital Instruments, Inc. ● 7240 BRITTMOORE RD ● Houston, TX 77092 Ph 713-688-8555 Fx 713-688-2228
Revision: 3 - 9 -
CSA Certification Markings:
Gauge Head Sensor
6.B ATEX Certificate and Tag:
ATEX Certification Markings:
Gauge Head Sensor
Note: In the event one of the components (gauge or sensor) fails, you can order the
replacement for a quick drop in replacement. When ordering, be sure to provide the
applicable serial # or certification requirements to ensure the replacement is acceptable.

Houston Digital Instruments, Inc. ● 7240 BRITTMOORE RD ● Houston, TX 77092 Ph 713-688-8555 Fx 713-688-2228
Revision: 3 - 10 -
SECTION VI
Warranty:
Houston Digital Instruments, Inc. (HDI) warrants for a period of one year from the date
of shipment, HDI's manufactured products to the extent that HDI will replace those parts
having defects in material or workmanship when used for the purpose or specification
HDI recommends.
HDI will replace or repair, as it deems necessary, any products covered by this warranty,
after HDI's examination discloses to its satisfaction, that in fact the products are defective
and an adjustment is required. If an adjustment is required, the amount of the adjustment
is the net sales price of the defective product. No allowances shall be made for labor or
expenses of repairing defective products or damage resulting from same. All products
accepted under the provisions of this warranty shall be shipped prepaid to HDI and
returned to the customer prepaid by HDI. All products not accepted under the provisions
of this warranty shall be shipped prepaid to HDI and returned freight collect.
HDI shall not be responsible for repair or replacement of products, resulting from
improper handling, storage, installation, misuse, negligence, or use in a manner contrary
to the recommendations of HDI.
HDI warrants only the products which it sells of Other Manufacturers to the extent of
their warranties. All warranty claims shall be made in writing to the nearest HDI office
or authorized factory representative. HDI makes no other warranty of any kind,
expressed or implied, and all implied warranties of merchantability or fitness for a
particular purpose which exceed HDI's afore-stated obligation are hereby disclaimed by
HDI and excluded from this warranty.
This warranty is non transferable and HDI shall not be liable for any damage, injury, loss
to property or persons resulting from the use of any HDI's products or equipment whether
such damage, injury or loss results from, or is caused by: manner of use, defects in
materials or workmanship or otherwise.

Houston Digital Instruments, Inc. ● 7240 BRITTMOORE RD ● Houston, TX 77092 Ph 713-688-8555 Fx 713-688-2228
Revision: 3 - 11 -