ROOTECH ACCURA 7500 User manual

ACCURA 7500
Integrated Digital Protection Relay
+ High Accuracy Power Meter
Communication User’s Manual[English]
Rev 1.0

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Notice
Symbols
Caution
Indicates the presence of dangerous voltage which can cause severe injury or
death to persons if proper precautions are not followed.
Warning
Alerts the user of the presence of hazards which can cause some injury to
persons, damage to property or damage to the device
itself, if proper
precautions are not followed.
Note
Indicates instructions for installation, operating and maintenance.
Indicates alternative voltage or current.
Indicates direct voltage or current.
Installation Considerations
The installation and operation of Accura 7500 should be performed only by qualified,
competent personnel that have received appropriate training and experience with high voltage
and current devices.
Caution
Failure to observe the following instructions may result in severe injury or death..
During normal operation, hazardous voltages are present on its terminal strips that
connect the PT(Potential Transformer), CT(Current Transformer), voltage input, power,
and external I/O circuits. The secondary of the PT/CT may generate fatal voltages/currents
resulting from the primary of the PT/CT.
Standard safety precautions should be followed while installing or maintaining the product,
including removing PT fuses and shorting CT secondaries.
Install the product in a switchgear cabinet to prevent users from accessing terminal strips
after completing wiring of the product.

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Warning
Observe the following instructions, or permanent damage may occur to the product.
Do not apply voltages and currents that exceed input ratings of PT and CT to the product.
Using the device for other purposes not specified by the manufacturer can cause severe
damage to the product.
Connect the ground terminal to the earth ground to protect the device from noise and
surge.
The terminal screw torque to be used has the following features.
- Barrier-type voltage terminal: 1.35Nm (14 kgf∙cm = 1.00 lbf∙ft) max.
- Barrier-type digital inputs/digital output terminal: 0.90Nm (9 kgf∙cm = 0.66 lbf∙ft) max.
About the Manual
Rootech Inc. reserves the right to make changes in the device specifications shown in this
User Guide without notice. Therefore, we recommend that customers should obtain the latest
information on specifications of the device before making orders.
In the absence of written agreements, Rootech Inc. assumes no liability for assistance with
product applications and the system design created by customers or legal issues, including
infringement of intellectual property arising from the use of devices described herein by
third-parties.
We are committed to providing accurate information in this document. However, we assume
no responsibility for any errors in the document and reserves the right to make changes
without notice.
Limitation of Liability
Where applicable law allows and does not prohibit or restrict such limitation, Rootech, Inc’s
liability for anything relating to this product shall be limited to the price paid for the product.

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Warranty
Rootech Inc. provides warrants for two years from the product receipt date only to the original
purchaser of the products and software that are sold or licensed by the company.
To obtain warranty service, the purchased products should be free from serious defects in
material and workmanship.
The software is provided in up-to-date versions, thus we do not offer any warranty for the
software product.
In order to make a product claim under the warranties described above, the original purchaser
should immediately contact Rootech headquarters. Upon receiving claims, Rootech will check
out the product either at where the purchaser is or at the company after receiving the product
from the customer, who is responsible for the cost of shipping the product. After inspecting
the product, we provide repair or replacement services for the product.
Rootech will decide at its discretion whether to repair or replace it or give a refund for the
product for when the warranty period for the product expired or issues related to the product
are not applicable for warranty terms and conditions.
Limitation of Warranty
The Warranty does not apply to uninterrupted or error-free operation of the product or cover
normal wear and tear of the product or costs caused by the removal, installation, or
troubleshooting of the customer's electrical systems.
Defects caused by any of the following factors are not covered under the warranty.
Improper use(alteration, accident, misuse, abuse) or failure to act in accordance with
installation, operation or maintenance instructions
Unauthorized modifications, changes or repair attempts
Failure to comply with applicable safety standards & regulations
Damages resulting from transporting or storing the product
Damages caused by the force majeure event, including fire, flood, earthquakes, storm
damage, overvoltage & lightning
If the original identification marks(trade-mark, serial number, etc.) have been defaced, altered,
or removed

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Rootech shall not be liable for any other claims except the claims made by customers, including
the original purchaser, his employees, agents, or contractors for any loss, damage, or expense
incurred related to the purchased product when the above warranty terms and conditions are
not fulfilled.
Any technical assistance provided by Rootech's personnel or representatives in system design
shall be deemed to be a suggestion. The original purchaser is responsible for determining the
feasibility of such suggestions and should conduct tests to prove their feasibility
It is the original purchaser’s responsibility to determine the suitability of any product and
associated documentation. The original purchaser should acknowledge that 100% uptime is
not guaranteed because of possible hardware or software defects. The original purchaser
should also recognize that such defects and failures may cause inaccuracies or malfunctions.
Any agency, corporate entity, or individual employees of Rootech or other companies is not
authorized to amend, modify or extend warranty in any way.

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Standard Compliance
Process Control Equipment
E324900

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Revision History
The following versions of the Accura 7500 Communication User Guide has been released.
Revision
Date
Description
Revision 1.0 November 11, 2020 First issue

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Contents
Chapter 1 Serial Communication..................................................................................................................11
Serial Communication.............................................................................................................................11
Accura 7500 Communication ................................................................................................................12
Chapter 2 Communication Wiring/Setup....................................................................................................14
Communication Wiring ..........................................................................................................................14
Communication Setup ............................................................................................................................15
Setup Mode ........................................................................................................................................................................16
Chapter 3 Modbus RTU Protocol..................................................................................................................18
Packet Field of Modbus RTU ......................................................................................................................................18
Slave Address Field .........................................................................................................................................................18
Function Field.....................................................................................................................................................................18
Data Field.............................................................................................................................................................................18
Error Check Field ..............................................................................................................................................................19
Exception Responses ......................................................................................................................................................19
Broadcast Packets.............................................................................................................................................................20
Packet Communication...........................................................................................................................21
Function 03: Read Holding Registers .....................................................................................................................21
Function 06: Write a Single Register to Meter..................................................................................................22
Function 16: Write Multiple Registers to Meter ...............................................................................................22
Reserved Registers...........................................................................................................................................................23
Invalid Registers ................................................................................................................................................................23
Chapter 4 Modbus RTU Map.........................................................................................................................24
Address Map Sections ............................................................................................................................24
Overview...............................................................................................................................................................................24
System information section.........................................................................................................................................26
Meter Part.................................................................................................................................................27
Configuration section.....................................................................................................................................................27
Measurement section.....................................................................................................................................................27
THD, K Factor......................................................................................................................................................................29
Extra energy section .......................................................................................................................................................29
Demand, Maximum, and Minimum section........................................................................................................30
Extra predicted demand section...............................................................................................................................31
Harmonic section .............................................................................................................................................................32
Vector diagram section†................................................................................................................................................33
Waveform section ............................................................................................................................................................34
Demand trend section ...................................................................................................................................................35
Reset section ......................................................................................................................................................................35

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Protection Part.........................................................................................................................................36
DIO Status and Control section ................................................................................................................................36
Measurement section†....................................................................................................................................................38
Reset section ......................................................................................................................................................................39
Maintenance section.......................................................................................................................................................39
Event Record section ......................................................................................................................................................40
Captured (Event) Waveform section†......................................................................................................................41
Auxiliary Function 1 Setup section..........................................................................................................................42
Auxiliary Function 2 Setup section..........................................................................................................................43
Digital Input Setup section..........................................................................................................................................44
Digital Output Setup section......................................................................................................................................45
DO-Relay Interconnection section 1.......................................................................................................................46
DI-DO Interconnection section..................................................................................................................................47
DO-Relay Interconnection section 2.......................................................................................................................47
OCR section ........................................................................................................................................................................48
NSOCR section ..................................................................................................................................................................48
OCGR section .....................................................................................................................................................................49
OVR section ........................................................................................................................................................................49
UVR section.........................................................................................................................................................................50
POR section.........................................................................................................................................................................50
NSOVR section ..................................................................................................................................................................51
OVGR section .....................................................................................................................................................................51
SGR section .........................................................................................................................................................................52
MOTOR Protection Section..........................................................................................................................................53
Short-form Data Block Section..................................................................................................................................54
Value Table................................................................................................................................................59
T1 : Date†(UINT32)..........................................................................................................................................................59
T2 : Time†(UINT32) .........................................................................................................................................................59
T3 : Event Type†.................................................................................................................................................................59
T4 : Interlock Function Setup .....................................................................................................................................62
T5 : Motor Operation Status.......................................................................................................................................62
T6 - T8 : Reserved............................................................................................................................................................62
T9 : Relay Function ..........................................................................................................................................................62
T10 : Aux. Relay Setup...................................................................................................................................................62
T11 : Digital Input Setup ..............................................................................................................................................63
T12 : DOUT Relay Type Setup....................................................................................................................................63
T13 : OCR, OCGR Relay Curve Setup .....................................................................................................................63
T14 : Fault, Pickup Status 1 .........................................................................................................................................63
T15 : Captured Waveform Data Scale†(INT16)..................................................................................................64
T16 : Fault, Pickup Status 2 .........................................................................................................................................64
T17 : DIN Input Type Setup ........................................................................................................................................64
Data formats ............................................................................................................................................65

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Measurement Value Calculation ...........................................................................................................68
Fixed Scale ...........................................................................................................................................................................68
Variable Scale .....................................................................................................................................................................68
APPENDIX A CRC-16 Calculation..................................................................................................................70
CRC-16 Generation..................................................................................................................................70
CRC Generation procedure..........................................................................................................................................70
APPENDIX B Modbus RTU C Code Example...............................................................................................72
Data Reception and CRC Generation & Checking.............................................................................72
Request Packet Generation .........................................................................................................................................72
Checking Response Packets........................................................................................................................................72
CRC functions.....................................................................................................................................................................73