Installation, Operation and Service Manual LKAT2 +24V
DynAmp, LLC WARRANTY
Items and components manufactured by DynAmp, LLC for permanent installation are
warranted to be free from defects in material and workmanship for a period of two (2) years
from the date of shipment.
Items and components manufactured by DynAmp, LLC for portable and temporary use in
more than one location are warranted to be free from defects in material and workmanship for
a period of eighteen (18) months from the date of shipment.
Items and components not manufactured and resold by DynAmp, LLC are warranted by their
manufacturer.
Warranty repair shall be, at DynAmp’s option, in the form of repair or replacement of the
defective items or components. Concerning warranty repairs, DynAmp, LLC will be
responsible for DynAmp provided time, material and transportation costs (shipping or travel).
Actual method of warranty repair / correction will be determined by DynAmp, LLC at
DynAmp’s sole option. Such warranty repair shall constitute a fulfillment of all DynAmp, LLC
liabilities in respect to said items and components. In no event shall DynAmp, LLC be liable
for consequential damages.
service by the purchaser or end user without the written permission of DynAmp, LLC is strictly
forbidden.
This manual is part of the complete set of product documentation that includes installation,
operation, and service instructions, drawings and test results. Users should evaluate the
information in the context of the complete set of product documentation and their particular
applications. DynAmp, LLC assumes no liability for any incidental, indirect, or consequential
damages arising from the use of this documentation.
While all information presented is believed to be reliable and in accordance with accepted
engineering practices, DynAmp, LLC makes no warranties as to the completeness of the
information.
Installation, Operation and Service Manual LKAT2 +24V
GENERAL
VOLTAGE
INSTALLATION
Hazard Warning!
HAZARDOUS
All installation, maintenance and service must be performed by qualified
technicians who are familiar with the warnings and instructions of this manual.
Use of the equipment in a manner not specified by the manuf acturer can impair
the protection provided within.
The enclosure cover must remain closed at all times during operation to ensure
safety of personnel. The cover may be opened using a screwdriver; however,
only authorized personnel or technicians should be allowed to open and service
the unit.
DynAmp, LLC does not assume liability for the customer’s failure t o comply with
the rules and requirements provided in this manual.
This equipment is designed to be connected to hazardous electric voltages.
Ignoring the installation precautions and warnings can result in severe p ersonal
injury or equipment damage.
To avoid the risk of electrical shock or fire, the safety instructions and guidelines
in this manual must be followed. The electrical specifications must not be
exceeded and the unit must be installed according to directions provided.
This equipment is intended for indoor or outdoor use. It should be mounted in a
well-ventilated area, away from high heat, dust, and corrosive atmosphere. The
ambient temperature must not exceed specified limits.
For mounting considerations that fall outside the recommended specifications
provided in this manual, the factory should be contacted for approval.
This unit is rated for installation category II and pollution degree 2.
Symbol
Identification:
General definitions of safety symbols used on equipment and manual.
Caution/Warning: Refer to accompanying documents for instructions.
Installation, Operation and Service Manual LKAT2 +24V
SAFETY
The Measuring Head is designed to be installed on high voltage bus bars. All interconnection
cables must be safely routed away from bus bars and high voltages. Do not allow any
interconnection cable to contact bus bars or high voltages.
Ignoring the installation precautions and warnings can result in severe personal injury or
equipment damage. The following are general guidelines to be followed during installation,
operation and service of the Metering Unit and Measuring Head.
•All installation, maintenance and service must be performed by qualified technicians who
are familiar with the warnings and instructions of this manual.
• Always follow all local and plant safety procedures.
• The enclosure cover must remain closed at all times during operation to ensure safety of
personnel. Only authorized personnel or technicians should be allowed to open and
service the unit.
• Units are not intrinsically safe. Do not place in explosive atmospheres.
• Service must be performed by qualified technicians only. If use of an oscilloscope
becomes necessary during servicing, the scope must be floating and ungrounded or
differential probe(s) must be used. The Metering Unit is isolated from the mains via the
power transformers. If a grounded scope is used, a hazardous condition is created since
current will flow through the probe to ground.
•Use of the equipment in a manner not specified by the manufacturer can impair the
protection provided within.
•If a binding screw is used for the mains earth connection, the binding screw must be size
M4 (No. 6) or larger.
DynAmp, LLC does not assume liability for the customer’s failure to comply with the rules and
requirements provided in this manual.
Installation, Operation and Service Manual LKAT2 +24V
DynAmp, LLC Customer Support & Service Assistance
For further assistance, contact DynAmp Customer Support at:
Americas:
Telephone: +1 614.871.6900 Fax: +1 614.871.6910
8:00 AM to 5:00 PM USA Eastern Time
From first Sunday in November to second Sunday in March – 13:00 GMT to 22:00 GMT
From second Sunday in March to first Sunday in November – 12:00 GMT to 21:00 GMT
After Hours Critical Service Emergency:
Telephone: +1 614.871.6906
5:00 PM to 8:00 AM USA Eastern Time
From first Sunday in November to second Sunday in March – 22:00 GMT to 13:00 GMT
From second Sunday in March to first Sunday in November – 21:00 GMT to 12:00 GMT
Installation, Operation and Service Manual LKAT2 +24V
TABLE OF CONTENTS
Paragraph Title Page
DynAmp, LLC WARRANTY ________________________________________________ iii
Hazard Warning! _________________________________________________________ v
SAFETY _______________________________________________________________ vii
DynAmp, LLC Customer Support & Service Assistance ________________________ ix
MANUAL REVISIONS _____________________________________________________ xi
TABLE OF CONTENTS ___________________________________________________ xiii
1. HANDLING AND STORAGE______________________________________________________ 1
Installation, Operation and Service Manual LKAT2 +24V
1. HANDLING AND STORAGE
DynAmp products are engineered and manufactured for use in industrial environments.
However, t hey contain sensitive electronic and mechanical components which may be
damaged and fail if not handled and stored properly. All products must be handled and stored
with the same care as any precision measurement instrument. Severe bumps or jolts may
damage internal parts and cause malfunction or premature failure. DynAmp products are
designed and assembled with conformal coating, shock mounting, and environmental seals,
when appropriate or when specified. However, this protection requires that the product must
be properly installed and operational before the protection is fully functional. Therefore,
adequate protection from humidity, shock, and temperature must be provided during handling
and storage prior to installation.
The handling and storage of equipment must be sufficient to meet the storage temperature
and humidity specifications of the product and to prevent any condensation or contact with
water or any other liquid. The storage location and container or crate must provide adequate
protection from precipitation (rain, snow, ice) and direct water contact. Adequate shelter must
be provided to prevent the accumulation of precipitation (rain, snow, ice) and water which can
lead to the deterioration or failure of shipping containers or crates and cause water ingress.
Storage in coastal or industrial areas subject to salt-laden or corrosive air or areas of winddriven sand or other abrasive dust must be adequate to prevent the deterioration or failure of
shipping containers or crates and cause ingress. Frequent inspection of storage areas and
storage containers or crates is required to ensure proper storage conditions are being
maintained.
If the shipping container or crate is opened and/or the equipment is removed for inspection
prior to installation, the equipment must be repackaged in the original undamaged container
or crate in the same manner as it was shipped to prevent environmental damage or placed in
a storage location that meets the required environmental and storage conditions.
General product storage temperature and humidity requirements:
Storage Temperature: -40°C to 70°C
-40°F to 158°F
Storage Humidity: Maximum 85%, non-condensing
DynAmp, LLC does not assume liability for the customer’s failure to comply with handling and
storage requirements.
For further assistance, contact DynAmp customer support.
Installation, Operation and Service Manual LKAT2 +24V
LKAT2 Measuring Head
2. PRODUCT DESCRIPTION
2.1 SYSTEM OVERVIEW
The LKAT2 combines accurate high current measurement with reverse and overcurrent
protection in a single rugged and cost effective system.
The next generation of DynAmp’s well proven OLOP
of accuracy and stability to accurately and reliably measure uni- and bi-directional DC as well
as AC bus currents.
The LKAT
2
is particularly well suited to measure power rectifier outputs for control and
protection purposes in electro-chemical processes such aluminum, chlorine, copper,
manganese, titanium, zinc, electroplating, etc.
TM
technology, LKAT2 offers a new level
LKAT
2
Metering Unit
KEY STANDARD FEATURES
True bi-directional performance. Ideal for difficult magnetic applications. No head position or
bus analysis needed.
Extremely compact with excellent environmental specifications for installation flexibility, inside
or outside.
Multiple, standard switch selectable measurement output signals including mA, mV and V.
Standard Accuracy Diagnostics “AD” continuously monitors system performance providing
both local LED and relay contact output.
Optional LKAT
2
Protection Extensions, (PE),
provides additional functionality for protecting high current rectifiers.
Standard Alarm provides reverse or over-current protection via an LED viewable at the
metering electronics and a dry contact relay output.
The LKAT
2
Metering Unit consists of a +24V power supply and Main pc board mounted
together on a steel U-chassis. Input, output, and power connections are made via pc board
edge connector plugs.
Installation, Operation and Service Manual LKAT2 +24V
Each standard LKAT
2
is delivered with the following
• A new, ruggedized two-piece Measuring Head with integrated mounting hardware and bus
bar corner (fiberglass angles). Each head half has its own cable for connection to the
metering electronics.
• Very compact Metering Electronics with one analog measurement output, one Accuracy
Diagnostics system status output and one configurable Alarm output for overcurrent or
reverse current protection.
• System output cable
• Power input cable
• Comprehensive User’s Manual
• Factory calibration data and graphs
• 2-year warranty for permanent installed systems
• Packaging suitable for air /ground transport
AVAILABLE OPTIONS
•Protection Extensions ( PE )
The PE option adds additional functionality for protecting high current rectifiers. This option is
either factory configured with a new system or can be added to LKAT
field. If added in the field, some field configuration may be required.
Second Freely Scalable Analog Output :
This second analog output is independently scaled and fully isolated from the standard LKAT
measurement output. In typical applications, it is scaled to provide accurate measurement
above the standard rectifier operating range for advanced protection purposes. For example,
the primary LKAT
2
output may be scaled to 50kA to provide the highest degree of accuracy
and resolution for normal rectifier control. The second PE output may be scaled to 75kA to
provide the information to intelligently manage overcurrent situations. Using this signal, the
rectifier control system could integrate overcurrent operation to allow 5 minutes at 110%, 1
minute at 120%, 10 sec at 140%.
Two Additional Protection Relays :
These relays bring total number of configurable relays to three. Each can be configured to
provide reverse or various degrees of overcurrent protection. Like the standard alarm, these
two additional PE alarms come with their own, independent local LED indication and relay
outputs.
•Digital current display ( 3 1/2 digit )
This option is mounted behind the clear front door of the metering electronics enclosure to
display either DC or RMS AC bus current locally.
maximum metering electronics ambient temperature to 50ºC. This option can also be added
to LKAT
2
Systems already in the field.
Please note that this option reduces the
•Custom Cable Lengths
Custom Measuring Head cable lengths can be provided but only at time of order. Note that
Measuring Head cable lengths cannot be changed after order or in the field because one end
is terminated inside the Measuring Head and the other end is terminated inside a fixed
connector.
Custom Signal and Mains cable lengths can be provided. Note that standard Signal and
Mains cables can be shortened or replaced with longer cables in the field.
Installation, Operation and Service Manual LKAT2 +24V
AVAILABLE ACCESSORIES
•Summing / Totalizing multiple LKAT systems
A dedicated external module is available for totalizing/ summing LKAT measurement signals.
This is typically used to provide a true ‘total’ current signal when multiple rectifiers ( with
individual LKAT systems ) are connected in parallel to provide a higher total current.
.
•LKAT Metering Unit Tester ( LKAT MUT )
The LKAT MUT is a portable tester used to verify the functionality of Metering Units for all
versions of the LKAT family of products.
Adapters included with the LKAT MUT allow the tester to be connected directly and check any
LKAT Metering Unit electronics.
The functions and parameters checked by the LKAT MUT include:
• Input / output sensitivity
• Trip point scaling
• Trip relay contacts
• Integrity of input / output harnesses and interconnections on Metering Unit
The tools / documentation required to use the LKAT Metering Unit Tester include :
• 4-1/2 digit DMM with 0.05% basic DC accuracy ( user provided )
• DMM Test probes ( user provided )
• Banana to banana cables ( 1black / 1 red )
• LKAT MUT Product Manual
More information on the LKAT MUT can be found at www.dynamp.com
Installation, Operation and Service Manual LKAT2 +24V
•Extended Warranty
For permanently installed systems, the standard 2-year warranty can be extended in 2-year
increments. This must be ordered less than 6 months after the original LKAT system is
shipped.
2.2 ADDITIONAL MEASURING HEAD DETAIL
LKAT2 Measuring Heads contain an arrangement of Hall Effect sensor ICs and signal
conditioning electronics. The tubular enclosure is constructed of flame retardant plastic with
an internal aluminum frame. Insulation from the bus is provided by the homogeneous
(sealed) construction of the head. In the event that the head enclosure components become
cracked, the bonding fails, or the weather-tight seal is broken in any way, a replacement head
must be substituted. The Measuring Head is not designed to be repaired.
2
LKAT
the corners of the bus bar and stainless steel bus bar mounting screws threaded into the
Measuring Head structure. Mounting hardware is supplied with each system. These screws
are adjusted to bus dimensions specified with each order. When properly installed, the
mounting hardware maintains the position of the Measuring Head in the event of temperature
fluctuation and / or bus vibration.
An interconnection cable assembly is integral to each half of the Measuring Head. Measuring
Heads with extra-long interconnection cables are also available - consult the factory for
details. Standard Measuring Head cable assemblies are terminated with keyed connectors to
ensure correct hookup. The interconnection cables from the Measuring Head are identified
as “A” and “B”. Connecting head cable “A” to Metering Unit “B” will not result in damage to
the head or electronics, but may degrade the calibration accuracy of the system.
Measuring Heads are mounted on the bus bar using fiberglass angles positioned on
2.3 ADDITIONAL METERING UNIT DETAIL
The Metering Unit electronics are housed in an environmentally rugged enclosure. The
enclosure cover must remain closed during normal operation.
The outside of the Metering Unit enclosure includes four receptacles for external connection
to the Measuring Head, the Metering Unit measurement signal(s) and relay outputs, and the
input of mains power. When properly mated with the associated cable assembly, these
connections are also environmentally protected.
Internally, all LKAT
board. These 2 PC boards are mounted to a steel chassis which is then mounted on a steel
panel housed in the enclosure. The Metering Unit enclosure door has a window made of
clear polycarbonate. This allows the user to view various LED (or LCD) status indicators
while the door is closed. For more information, refer to the “Theory of Operation” section of
this manual.
There are two optional pc board assemblies that may be added onto the Main pc board in the
2
LKAT
Metering Unit:
• The Protection Extensions ( PE ) pc board assembly
• The Display pc board assembly.
One or both of these pc board assemblies may be added to an LKAT
field. It is not mandatory that they be factory installed and/or calibrated. The optional pc
board assemblies may be calibrated on site, using the LKAT
measurement.
2
Metering Units include both a Power Supply pc board and a Main pc
Installation, Operation and Service Manual LKAT2 +24V
Main PC Board
Assembly
with PE PC Board
Assembly
Isolated Output
1
+1 for 2 total
Operational Status LEDs & Relay Contacts
1
+0 for 1 total
Overcurrent / Reverse Trip Status LEDs & Relay
Contacts
2.4 ADDITIONAL INDICATOR AND OUTPUT DETAIL
As noted on the specifications page, The LKAT2 System Metering Unit includes several visual
indicators. These include:
•Accuracy Diagnostics (operational status) LEDs: green = OK, red = system problem (see
Section - “Theory of Operation”).
•Over / Reverse Current Trip status LEDs: green = measured current does not exceed the
setpoint, red = measured current exceeds the setpoint.
•(Optional) Illuminated LCD digital display of measured current.
Available via the Metering Unit output cable:
•Isolated signal output proportional to bus current being measured. This output may be
configured for various zero and full-scale values.
•Normally open and normally closed relay contacts indicate (AD) Accuracy Diagnostics
operational status (same as green and red LEDs).
•Normally open and normally closed relay contacts indicate over / reverse current trip
status (same as green and red LEDs). For failsafe operation, the relay coil is energized in
the normal condition (no over / reverse trip).
The table below lists the features associated with the Main and PE pc board assemblies.
Table 2.1
Main and PE PC Board Assembly Features
1 +2 for 3 total
2
Checking field calibration of LKAT
with calibration accuracy of 0.1% full-scale or better. Contact DynAmp, LLC for calibration of
the LKAT
2
System. Refer to “Maintenance and Spare Parts” section for more information.
Systems requires use of a reference current transducer
2.5 INTERCONNE CTION CABLE DETAIL
The LKAT2 System is supplied with two cable assemblies in addition to those connected to the
Measuring Head.
The power input cable assembly. A keyed circular connector terminates one end for
connection to the Metering Electronics. The other end is unterminated for connection to the
power source by the user during installation.
The system output cable assembly. A keyed circular connector terminates one end for
connection to the Metering Electronics. The other end is unterminated for connection to the
power source by the user during installation. The system output cable is a 17-conductor type.
However, only 8 of the 17 conductors are used when the optional PE pc board assembly is
NOT installed. The unused conductors may be trimmed flush to cable jacket. The user
connects this cable from the Metering Unit to the appropriate inputs during installation.
over current (+5…+100% of full-scale) or
reverse current (-5%...-100% of full-scale).
Red indicates measured current exceeds Trip
current exceeds Trip Setpoint or mains power
lost.
Installation, Operation and Service Manual LKAT2 +24V
OPTIONAL DISPLAY
Digital Display of Bus Current in kA units
3 ½ Digit Green LCD ±2% Full-scale
GENERAL
Input Power
be connected without any wiring changes)
Working Voltage: Signal Output to Metering Unit
450Vrms
ENVIRONMENTAL
Operating Ambient Temperature Range of Metering
-10°C to 60°C
Operating Ambient Temperature Range of
Measuring Head
-20°C to 80°C
(-4°F to 176°F)
Environmental rating: Measuring Head and cable
connection at Head
Environmental rating: Metering Unit and cable
connection at Metering Unit
Table 3.1
LKAT2 System Specifications ( subject to change without notice ), continued
OPTIONAL PROTECTION EXTENSIONS ( PE )
PE Full Scale Measuring Range
independently and isolated from main output)
PE analog output configuration and performance
specifications
PE Over / Reverse Current Trip Setpoints -Qty. (2) Field configurable
Displayed Value (configurable) DC or True RMS
NOTE: Optional display reduces maximum ambient temperature of metering unit to 50°C
(any voltage within the specified range can
Burden on Mains (max) 30 VA
Low Voltage Circuit
Working Voltage: Bus to Metering Unit Low Voltage
Circuit
Working Voltage: Mains Supply to Metering Unit
Low Voltage Circuit
Working Voltage: Mains Supply to chassis 264Vrms
(scaled
±5kA to ±200kA
measuring ranges > 100kA )
Same as Main output above with all configuration
and scaling independent from main output
Function and specification same as Main Over /
Reverse above with independent LEDs,
configurations, scalings and outputs
( Contact factory for full-scale
18 - 36Vdc
1500Vdc
264Vrms
Working Voltage: Output to chassis 450Vrms
Isolation : Head surface to signal outputs 6000Vrms for 1 minute
Isolation : Mains supply to signal outputs 1000Vrms for 1 minute
Isolation : Mains or signal output to chassis 2000Vrms for 1minute
Installation Category II
Pollution Degree 2
Installation, Operation and Service Manual LKAT2 +24V
4. INSTALLATION
4.1 HANDLING PRE CAUTIONS
LKAT2 Systems should be handled with the same care as any precision measuring
instrument. Severe jolts or bumps to the Measuring Head or Metering Unit may cause
movement of internal parts, and possibly a malfunction. Personnel involved in the
installation should be familiar with the technical terms, warnings, and instructions in
this manual, and all plant safety rules, and be able to follow these.
The complete system should be inspected for shipping damage at the earliest opportunity.
Visible damage must be reported to the carrier immediately. Concealed damage (not evident
until the system is operated) must be reported to DynAmp, LLC immediately.
4.2 INST ALLATION CONSIDERATIONS
Read the following before mounting the head:
1. The Measuring Head is designed to be installed on high voltage bus bars. All
interconnection cables must be safely routed away from bus bars and high voltages. Do
not allow any interconnection cable to contact bus bars or high voltages. Ignoring the
installation precautions and warnings can result in severe personal injury or equipment
damage.
2. Always follow all local and plant safety procedures when the unit is to be installed on a live
bus.
3. Choose a mounting location for the head where the ambient air temperature does not
exceed the specified temperature limits. The LKAT
doors or outdoors, but should be kept away from extreme heat and solvents. Head
installations in direct sunlight are not recommended, as excessive temperature rise could
result in measurement error or damage to the head enclosure. If the head is to be
installed in an especially harsh environment, please contact the factory to discuss special
requirements.
4. No part of the head or Metering Unit should be submerged under water.
5. The head must be installed with proper polarity. An arrow indicates the direction that
conventional bus current must flow through the aperture (+) to (-). No damage will occur if
the head is reversed, but the system output will indicate current flow in the reverse
direction.
6. Measuring Heads are shipped in matched halves. Make sure that the same serial number
is present on both halves of the Measuring Head and the Metering Unit. The two head
halves should mate squarely and evenly without forcing or twisting.
7. The Measuring Head is not grounded; however, the head cables should be disconnected
from the Metering Unit prior to installation or maintenance to minimize the possibility of
electrical shock.
8. Measuring Heads are shipped with mounting hardware. The mounting screws may require
adjustment for appropriate position and holding force on the bus. Refer to Outline &
Mounting – LKAT
2
Measuring Head drawing.
Whenever possible, the head should be installed on the longest straight run of the bus that is
available in an area free of other bus structures. The status accuracy diagnostics LEDs and
relay contacts indicate proper operation in a given head location.
Installation, Operation and Service Manual LKAT2 +24V
3/16” hex wrench (included with Measuring Head)
Drill, drill bits, mou nting hardware, screwdrivers, wrenches, etc.
Cable puller, cable ties, ladder, etc.
4.3 OFF-BUS FUNCTIONAL CHECK (OPTIONAL)
After unpacking the LKAT2 System (but prior to installation), the following functional check of
the system is recommended:
1. Locate a convenient temporary power source for the LKAT
be in the location where the system will be installed. The power source must be in the
range 18-36Vdc. The system draws a maximum of 30 volt-amperes.
2. Refer to the drawing “Wiring Diagram, LKAT
2
System” included at the end of this manual.
Attach a suitable connector to the unterminated end of the input power cable assembly for
connection to the power source to be used for this check.
3. Connect the Measuring Head cables A & B to the Metering Unit.
4. Connect the power input cable assembly to the Metering Unit and energize the unit.
5. Observe the LEDs on the Main pc board assembly. If the LEDs light green, the system is
functioning properly. If LED (Accuracy Diagnostics “AD”) lights red, skip to
“Troubleshooting an Accuracy Diagnostics Fault Indication” in the “Theory of Operation”
section of this manual. If LED (Trip 1) lights red, make measurements and complete the
form “LKAT
2
Diagnostic Measurements Form – Zero Primary Current” and contact the
factory.
Refer to Form 1 – Zero Primary Current. Allow the system one hour to stabilize prior to
making measurements. Make measurements and record data shown on the form. File the
completed test form for future reference. It is OK to make these measurements away from
location where the LKAT
2
System will be installed, but this should be noted on the form.
2
System. This may or may not
4.4 MEASURING HEAD INSTALLATION
The head halves are mated together around the bus. The Measuring Head is comp rised of
two “L” shaped halves. Each half is identified with a serial number w hi ch must match followed
by an “A” or “B”. One interconnection cable exits from each corner box on each half. The two
halves are held together by four locking screws which are installed after the head is securely
positioned around the bus bar.
When the Measuring Head is installed on a running (“horizontal”) bus, the head
interconnection cable assemblies should exit the corner enclosures on bottom side of the bus
bar. This reduces chances of ingress by pollutants and minimizes heating of the head
electronics by the bus.
For rising (“vertical”) busses, the head interconnection cables may be located on any side of
the bus, depending on mechanical and thermal considerations. Avoid mounting boxes above
vertical bus. The head should be mounted on the bus bar so conventional (+) to (-) current
flows in the direction of the arrow on the Measuring Head.
The following tools and materials may be required for installation:
Installation, Operation and Service Manual LKAT2 +24V
Front Vie w
Installation Confi gura t ion Side View
The following is the recommended sequence for installing the Measuring Head:
1. Refer to the Outline and Mounting drawing for the Measuring Head at the end of this
manual.
2. Determine the position where the Measuring Head will be installed. Bus bar(s) should be
free from grease and dust for the best adhesion of the LKAT
2
90° mounting angles to the
bus bar(s).
3. Connect the head cable assemblies to the Metering Unit.
4. Remove the backing from the adhesive foam strips on the fiberglass mounting angles.
Align the mounting angles in position on the corners of the bus bar in the desired location.
5. Position the two “L-shaped” head halves around the bus and the mounting angles. Mate
the two halves, pressing them together until the tubes bottom out on the elbows.
6. Install the four locking screws on the outside of the square tubes adjacent to the place
where the head halves split apart. Do not over tighten the locking screws. Refer to
Outline & Mounting – LKAT
2
Measuring Head drawing.
7. Tighten the bus mounting screws a few turns at a time in a circular pattern around the
aperture of the head, on the front side, then on back side of the head. For most
applications, the head should be centered on the bus bar. The bus mounting screws
should press against the foam tape on the mounting angle surface on the outside of the
bus bar. Refer to Outline & Mounting – LKAT
2
Measuring Head drawing. Do not
overtighten bus mounting screws.
8. Route the head interconnection cables away from the bus and other high voltages.
9. Connect the power cable assembly to appropriate power source and LKAT
2
Metering Unit.
4.5 M E TE RING UNIT INSTALLATION
The location of the Metering Unit should be determined by the following factors:
1. Ambient air temperature must stay in the specified range at all times.
2. The location should not be exposed to direct sunlight.
Installation, Operation and Service Manual LKAT2 +24V
3. The location should be within reach of the head cables supplied with the system.
Standard head cable length is 33 feet (10 meters). Extra-long head cables may also be
ordered for special applications.
4. Route interconnection cables away from bus and other high voltages.
Refer to Metering Unit Outline & Mounting drawing at the end of this manual. Anchor the
cabinet in the desired location after ensuring adequate cable reach.
5. Connect Measuring Head cable assemblies to the Metering Unit.
6. Refer to the LKAT
2
System Wiring Diagram. The output cable assembly consists of
20AWG shielded twisted pair cable (8 pairs) with 17 (one contact position in output
connector is unused) position circular connector on one end, and stripped, tinned wires on
the other end. The twisted wire pairs are jacketed with black and white PVC. Each pair
has the pair number imprinted on the jacket. Connect the output cable assembly wires to
the appropriate points in the process electronics system.
7. A 3-conductor power cable is supplied with the system. Connect power cable to the
Metering Unit.
4.6 SYS TEM CHE CKO UT
Recheck all wiring connections against the drawings to ensure proper installation. Energize
the LKAT
2
System. Confirm that the green status LEDs are illuminated. If accuracy
diagnostic LED lights red, skip to “Troubleshooting an Accuracy Diagnostics Fault Indication”
in the “Theory of Operation” section of this manual
Energize the rectifier to the desired test current. Calculate the expected Metering Unit output
signal magnitude at the test current.
The measured Metering Unit output signal magnitude should be equal to (or very close to) the
expected value that was calculated.
If the Digital Display option is included in the Metering Unit, the displayed kA level should also
be equal to (or very close to) the expected value that was calculated.
Refer to “SPECIFICATIONS” section of this manual for more information.
Photocopy the appropriate LKAT
2
Diagnostic Measurements Forms. Form 1 is for diagnostic
measurements at zero bus current (with the Measuring Head on or off the bus). Form 2 is for
diagnostic measurements with the Measuring Head installed on the bus with the bus
energized. Follow the directions to measure and record necessary information.
• These forms are intended to help keep accurate records of LKAT2 functional tests.
• This information may prove valuable in the event of a malfunction.
• These measurements do not constitute system calibration.
• Space is provided for the recording of three sets of readings.
• Voltages may vary slightly with temperature extremes.
• System performance will typically remain within nominal specifications when measured
levels fall within the acceptable limits shown on the forms.
• Levels must be measured and recorded under test conditions shown on the forms.
• The Metering Unit cover must be open during system checkout, as all measurements
are made inside Metering Unit on Main pc board terminal blocks. The cover should
remain firmly closed during normal operation.
Always complete these forms in full before contacting the factory.
Installation, Operation and Service Manual LKAT2 +24V
5. THEORY OF OPERATION
5.1 GENERAL
The LKAT2 System uses open-loop, open-path (OLOP) technology to convert the magnetic
field associated with a current carrying conductor into an isolated milliampere current loop
output. This output is scaled to be proportional to the primary conductor current. In addition,
a local digital display of the primary bus current (in kiloAmperes) is visible when the optional
RMS Display pc board is added to Metering Unit.
Each Measuring Head is a sealed unit and is not designed for repair in the field. However, a
working knowledge of the LKAT
accurate diagnosis in the event of problems.
5.2 OLOP TECHNOLOGY
The term “open-loop” means that the magnetic circuit does not generate an opposing
magnetic field to null the field produced by the primary conductor inside the Measuring Head.
The term “open-path” indicates that the sensor is an air-core design, without magnetic core
material.
The LKAT
(magnetic flux density) around any closed path is equal to µ
current)”. In practical terms, this means that integrating a closed path around a primary
conductor will yield a value proportional to the net primary current.
This integration is implemented using a specific array of Hall Effect ICs. The LKAT
effectively minimizes errors typically present in other open-loop sensors: zero drift, thermal
drift, position sensitivity, and susceptibility to external magnetic fields. The absence of a
magnetic core practically eliminates errors due to saturation, hysteresis, and core set
(remanence) commonly associated with ferrite material.
A generalized block diagram of the LKAT
2
System operation is based on Ampere’s Law, which states: “the line integ ral of B
2
System theory of operation will help facilitate timely and
Installation, Operation and Service Manual LKAT2 +24V
Hall IC Array
Head Half A
Signal
Conditioning
& Scaling
Hall IC Array
Head Half B
Signal
Conditioning
& Scaling
SENSOR HEAD
+12Vdc
+15Vdc
POWER SUPPLY PCB
Summing
Amplifier
Gain Adjust
Isolation
Current
Loop
DC Bias
Metering Unit PCB Assy
DC Bias
V
I
Comparator
Status LEDs
Relay Contacts
DC Bias
Comparator
Status LEDs
Relay Contacts
PROTECTION
EXTENSIONS
PCB (OPTIONAL)
Note: This PCB is very
similar to the Main PCB.
Display Gain &
Zero Adj.
RMS to DC
Digital Display
Display PCB (Optional)
19.99
Figure 5.1
Block Diagram of the LKAT2 System
5.3 SYSTEM FUNCTIONAL DESCRIPTION
The flux density associated with the primary current is sensed by arrays of Hall ICs in the
Measuring Head. The outputs of these devices are summed and filtered, then transmitted to
the Metering Unit where these signals are dc biased and scaled. The Accuracy Diagnostics
status LEDs and relay contacts are driven by a signal input that compares the various Hall
groups with voltage setpoints. When the Hall group signal exceeds the reference, the green
LED will go out and the red LED will illuminate. The relay coil will change state under the
same conditions. The Trip Setpoint LEDs and relay contacts operate in a similar manner.
Installation, Operation and Service Manual LKAT2 +24V
Main PCB LED is a RED / GREEN the Accuracy Diagno s t ics status LED. This LED indicator
and Main PCB relay CR2 contacts may be used to monitor the following conditions:
• Measuring Head imbalance
• Power supply failure
• Measuring Head disconnected
• Sensor electronics failure
• Other circuit failures causing loss of measurement accuracy
Occurrence of one or more of the conditions above will change the state of the CR2 relay coil,
changing the state of the contacts and changing the LED indication from green to red. Refer
to the section “Troubleshooting an Accuracy Diagnostics Fault Indication” in this section for
more information about determining the cause and eliminating a fault condition.
Refer to section “Failsafe” / “Non-Failsafe” Configuration in this chapter for more information
about Alarm Relays.
5.4 LKAT2 METERING UNIT
Refer to drawings in the back of this manual.
Input power connects to the Power Supply pc board assembly. The power supply pc board
includes a non-replaceable slo-blo type fuse, in-rush and overcurrent protection, as well as
MOV overvoltage clamping. The power supply provides outputs of ±15Vdc and +12Vdc
required by the system electronics. These outputs connect to the Main pc board assembly via
a short wire harness.
Connections to the Measuring Head are made via the Main pc board assembly.
5.5 LKAT2 MEASURING HEAD INTERCHANGEABILITY
DO NOT connect LKAT Classic or LKAT Plus Measuring Head to an LKAT2 Metering Unit –
doing so will damage the Measuring Head.
2
LKAT
Metering Unit. However, the LKAT
Measuring Heads of various sizes will operate properly when connected to the LKAT2
2
System is factory calibrated as a system. As a result,
optimal measurement accuracy is achieved when the Metering Unit is connected to the head
it was calibrated with, and installed on the size bus bar it was designed for.
5.6 TROUBLESHOO TING AN ACCURACY DIAGNOSTICS FAULT
INDICATION
A problem may be detected when the LKAT2 System is energized with A and B head cables
connected to the Metering Unit. When the Main PCB AD status LED illuminates RED and /
or Main PCB CR2 status relay coil changes state, a possible fault condition has been
detected. This is true whether or not the Measuring Head is installed on the bus. The
following table is intended to help the user determine and eliminate the cause of the fault.
Installation, Operation and Service Manual LKAT2 +24V
ON
OFF
Open
X
X
System operating
OFF
OFF
Closed
X X No input power
Verify input power connection
OFF
OFF
Closed
X
X
DC power supply
Verify DC power on main PCB
Head halves
disconnected
Verify head interconnections at Metering
Unit
Adjust position of head for green ON, red
OFF
Measure head input signals at zero bus
substitute known good Measuring Head
OFF
ON
Closed
X X Other problem
Contact factory
IMPORTANT NOTE
DynAmp, LLC assumes no responsibility for the accuracy of LKAT2 Systems ca librated
by any person other than a DynAmp, LLC Technician.
Table 5.1
Troubleshooting an Accuracy Diagnostics Fault Indication
Possible problem
Main
Main
Green LED
Contact
Red LED
BUS ON
BUS OFF
P3-3 to P3-5
Action / Check
OFF ON Closed X X
OFF ON Closed X Head imbalance
OFF ON Closed X X
Measuring Head
malfunction
current; output should be < 5mVdc;
5.7 SYSTEM CALIBRATION OVERVIEW
DynAmp does not specify exact required intervals of calibration for its products.
The end user of the product is responsible for identifying the appropriate interval between
calibrations. The intervals should be determined based on the following factors:
• Requirements of a Quality Management System
• Accuracy and permissible limits of errors
• Purpose and usage
• Experience with similar products
• Manufacturer’s recommendations
• Stability of the product
• Past history
• Other characteristics of the product
Reference: "ISO/IEC 17025:2017, General requirements for the competence of testing and
calibration laboratories" and Laboratory Accreditation Bureau "Guidance for Documenting and
Implementing ISO/IEC 17025:2005 and Laboratory Guidance."
As a guideline, DynAmp recommends a 24-month interval of calibration for all permanently
installed products and a 12-month interval of calibration for all products used in portable
applications.
Installation, Operation and Service Manual LKAT2 +24V
IMPORTANT NOTE
g calibration must review
Generally, system calibration compares the output of the device under test (“DUT”) to a
reference.
The best calibration method is to return LKAT
bus in a very controlled environment with extremely stable and accurately measured current.
This re qu ires that the LKAT
2
Measuring Head be removed from process bus. The head and
2
Systems to the factory for calibration on a test
associated Metering Unit must be returned together, and should have the same serial
number. The signal output and input power cable assemblies do not need to be returned for
factory calibration. Specific details of factory calibration are beyond the scope of this manual.
Field calibration is possible using a 0.1% accurate current measurement system, such as the
DynAmp LKP, LKCO or Opti-Cal as a reference. Due to significantly larger size and mass, it
may be difficult to install a comparably rated LKP Measuring Head in on the same bus as the
2
LKAT
. An existing LKCO or DynAmp’s portable Opti-Cal system is better suited for this
purpose.
Field calibration accuracy depends on the stability of the test bus current, the accuracy of the
reference current measurement system and ammeters, as well as the linearity of the LKAT
2
System.
5.8 CALIBRATION ADJUSTMENTS
To avoid injury and/or electrical shock, personnel performin
and observe all hazard warnings and safety precautions stated throughout this product
manual.
2
LKAT
System calibration adjustments are summarized below.
All Bias and Zero adjustments are made at zero bus current.
All Scaling and Gain adjustments are typically made at full-scale current.
Refer to pc board assembly drawings at the end of this manual for location of switches and
potentiometers, as well as tables listing proper switch settings. Except for step 1) below, each
table is shown on the appropriate pc board assembly drawing.
Forms 1 and 2 are used to check and record system power supply and channel voltages.
Main PCB – Current Loop Output
Installation, Operation and Service Manual LKAT2 +24V
NOTE
The Optional PE and/or RMS Display pc board assemblies may be added, configured
and calibrated in the field . In this case, the Main pc board asse mbly output signal is used
Optional PE PCB – Current Loop Output
• Output Bias (coarse) : SW4
• Output Type : SW5
• Output Gain (coarse) : SW1 and SW2
• Output Bias (fine) : Trimpot
• Output Gain (fine) : Trimpot
Optional PE PCB – Trip 2 & 3 Setpoints
• Trip 2 Protection Polarity : SW3
• Trip 2 Setpoint : R33 (medium) and R46 (fine)
• Trip 3 Protection Polarity : SW3
• Trip 3 Setpoint : R34 (medium) and R47 (fine)
Optional RMS Display PCB – Display
• Decimal Point position
• DPM Mode
• RMS Signal Conditionin g Options : SW1F, G, & H ( SW1-6, 7, & 8)
Installation, Operation and Service Manual LKAT2 +24V
New Trip Current
New V
=
Old Trip Current
X Old V
Example:
Old V
STPT
= 7V
Old Trip Current
= 70kA
New Trip Current
= 80kA
80kA
X 7V
= 8V (New V
STPT
)
70kA
1
TP6
2
TP2
3
TP3
Use TP0 for zero volt reference (circuit common) for voltage measurements for trip setpoint
5.9 FI E LD CO NFIGURATION OF TRIP SETPOINTS
Trip setpoints may be re-configured on site for any level between 5% and 100% of full-scale.
The trip polarity may also be re-configured on site. However, the Accuracy Diagnostics trip
setpoint should not be adjusted without consulting the factory.
Refer to assembly drawings for the Main pc board and PE pc board (optional) included at the
end of this manual. To change trip polarity adjust SW2A and SW2B according to the table on
the assembly drawing.
The trip setpoint is proportional to the current where the trip will occur: “Trip Current” – from
Metering Unit nameplate.
The easiest method to check or change trip setpoints is to use the DynAmp LKAT MUT
system which is specifically designed to simplify this process as well as verify proper
operation afterwards.
To configure the trip setpoint without the LKAT MUT or complete test stand, the following
method can be used.
Refer to Table 5.2, “Trip Configuration Details”. Measure t he existing setpoint voltage (V
use the equation below to calculate the new setpoint voltage. Adjust coarse and fine
potentiometers to produce calculated New V
STPT.
STPT
);
STPT
STPT
Table 5.2
Trip Configuration Details
Trip Circuit V
(Main)
(PE)*
(PE)*
configuration.
STPT
(Main)
(PE)*
(PE)*
Location
Medium Adjust
Trimpot
R91 R98
R33 R46
R34 R47
* Optional
NOTE
The LKAT2 is supplied with factory configured trip setpoints configured as specified in the
LKAT2 Worksheet at the time of order. If the trip setpoints are reconfigured in the field, the
customer must realize that the trip setpoints shown on the LKAT2 Metering Unit nameplate
will no longer be correct. In this case, DynAmp suggests that the nameplate be changed to
reflect the new trip setpoint (following reconfiguration).
Installation, Operation and Service Manual LKAT2 +24V
No low pass filtering
OFF
OFF
OFF
ON
5.10 EARTH GROUNDI NG
Here is a detailed description of the Earth Ground connection path:
1. The input power cable assembly connects CONN4 to the mains power.
2
2. Refer to the LKAT
3. The earth ground wire connects from CONN4 to the FLTR1 metal case only. The
FLTR1 metal enclosure is not connected to copper foil traces on the Power Supply PC
Board Assembly, the steel standoff inserts or the steel PCB mounting bracket.
4. The Earth Ground connection is only used to shunt common mode noise to earth.
There is no electrical connection from any part of the LKAT Main PCB or its optional daughter
PCBs to Earth / Chassis ground or the steel PCB mounting bracket or panel. There is no
electrical connection between the steel PCB mounting bracket or panel to Earth Ground.
System Wiring Diagram and wire system accordingly.
IMPORTANT NOTE
5.11 CONFIGURING THE LOW PASS FILTER
The LKAT2 System includes a two pole configurable low pass filter. This filter may be enabled
without affecting the scaling of the output in the pass band. The frequency response of the
2
LKAT
Refer to the Main pc board assembly drawing at the end this manual. To configure the low
pass filter, set switches as shown in the table below.
330 Hz cutoff OFF OFF ON OFF
660 Hz cutoff ON ON ON OFF
without the low pass filter activated is shown in Figure 3.1.
Installation, Operation and Service Manual LKAT2 +24V
Non-Failsafe Metering Unit Configuration
POWER ON
TRIPPED
5.12 “FAILSAFE” / “NON-FAILSAFE” CONFIGURATION
The LKAT2 System relay outputs are failsafe as factory configured. When the system is
energized, all relay coils are energized and all contacts change state; that is, open contacts
close and closed contacts open. During any alarm condition, relay coils de-energize, which
changes the state of the relay contacts.
In the failsafe configuration, loss of input power to the LKAT
alarm relay coils. This causes the relay contacts to change state and indicate an alarm
condition.
For some applications, the user requires that Trip1 to be “non-failsafe”. That is, the system
should not produce an alarm when there is loss of input power. Alarm conditions other than
loss of input power must continue to result in an alarm. Trip1 relay contacts can be configured
for Non-Failsafe operation. AD relay contacts are failsafe only. Trip2 and Trip3 relay contacts
(present on optional PE PCB assembly) are failsafe only.
Table 5.4 shows the status of the LKAT
2
alarm relay contacts. The alarm relay contact
condition is shown as it exists at the customer connections to the metering unit.
2
To convert the LKAT
System Trip1 to non-failsafe operation requires modification of the
Main pc board assembly, and modification of an internal wiring harness. Contact factory.
Refer to the Main pc board assembly drawing at the end of this manual.
Table 5.4
LKAT2 Alarm Relay Status
(As found at Customer Connection to Metering Unit)
2
Metering Unit de-energizes the
Alarm
Name
Contact Set
POWER
OFF
POWER ON
NORMAL
Trip2 P9-6 to P9-8 Closed Open Closed
P9-6 to P9-7 Open Closed Open
Trip3 P9-3 to P9-5 Closed Open Closed
P9-3 to P9-4 Open Closed Open
Trip1
P3-6 to P3-8
P3-6 to P3-7
Open
Closed
Open Closed
Closed Open
AD P3-3 to P3-5 Closed Open Closed
P3-3 to P3-4 Open Closed Open
Installation, Operation and Service Manual LKAT2 +24V
IMPORTANT NOTE:
If Main pc board LED (AD Status LED) is illuminated RED and / or the status relay
manual.
CAUTION
To avoid the risk of shock and electrocution, always disconnect all cable assemblies
6. MAINTENANCE & SPARE PARTS
6.1 PERIODIC MAINTENANCE
As is true with any electronic system, proper maintenance will tend to prolong the service life.
DynAmp, LLC recommends the following program be performed at the recommended interval
to prevent or detect damage to the LKAT
Always use appropriate measures to correct any problems found. Following the suggested
maintenance schedule may assist in early diagnosis of problem(s) to minimize repairs and
down time.
coil de-energizes, a fault condition may exist in the LKAT2 electronics. When this
occurs, the system may require immediate attention. Refer to “Troubleshooting an
Accuracy Diagnostics Fault Indication”, in the “Theory of Operation” section of this
2
System and to ensure reliable performance.
6.2 ANNUAL MAINTENANCE
Refer to the “Calibration” section of this manual for calibration intervals.
If possible, perform the steps described in section titled “System Checkout” in the “Installation”
section of this manual at least once per year to verify performance of the LKAT
may help to prevent or detect damage to the system and to ensure reliable performance. Use
appropriate measures to correct any problems found. If LKAT
2
System equipment is exposed
to extreme temperatures, DynAmp, LLC recommends these steps be performed during the
hottest time of the year.
In addition, the following steps should be performed once each year as part of annual
maintenance:
1. Visually inspect Measuring Head and interconnection cable for evidence of severe
overheating, cracks, separation of bonded surfaces, or excessive corrosion. Record any
suspect conditions.
2. Inspect the Measuring Head mounting screws and adjust as needed.
3. Visually inspect Metering Unit for evidence of severe overheating, corrosion, or
condensation. Record any suspect conditions and take appropriate action.
4. Clean as necessary; remove any oil or grease with a mild detergent. Do not use
abrasives or strong chemical solvents as they may damage the cables or erase the silkscreen markings from the Metering Unit.
5. Disconnect power to the system before servicing.
2
System. This
before performing any cleaning on the Metering Unit.
Installation, Operation and Service Manual LKAT2 +24V
Angle, LKAT2 Mounting 100mm
46039
8 (each)
Screw , LKAT2 mounting SHCS 1/4-20 X 3”
46028
2 (each)
Spare System
Complete System
(Head & Metering Unit calibrated as system)
*
TBD
Metering Unit
**
TBD
Measuring Head
**
TBD
6.3 S PARE PART S
The following table lists the minimum recommended quantities for spare parts for the LKAT2
System. As spares are used, replacements should be ordered. Since continuous operation
of high-current measurement systems is often critical, stocking spare parts should be given
high priority.
Some cable assemblies for the LKAT
cup connectors assembled with adhesive-lined shrink tubing covering the connector shell. If
connector(s) are severed from the associated cable assembly, field installable replacement
connectors may be purchased. These connectors may also be installed after routing head
interconnection cables in conduit. Over-molded replacement cable assemblies may be
purchased for the power input and output cables. Head cable connector(s) must be replaced
by field installable type(s), or with a new head. Refer to Spare Parts List Table 6.1
The LKAT
2
System Measuring Heads require special repair procedures and materials.
However, the heads are very reliable and should require little or no repair over its service life.
Please refer to the nearest authorized DynAmp, LLC service center for information on repairs.
DESCRIPTION ITEM NO. RECOMMENDED
2
System include circular connectors. Others use solder