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Single Phase BS Type Keypad Prepayment Meter
Technical Manual
General Safety Rules
DDSY1088 Single Phase Keypad Prepayment Meter owns advantages of simple measurement, simple installation and simple operation. But to avoid personal injury and other products related to the meter, it is suggested that this manual should be carefully read, which is better for usage before being installed, detected, operated and used.
While the designing and producing of DDSY1088 Single Phase  Keypad Prepayment Meter, its solidity and reliability and users’ safety and convenience have been already fully considered. The The METER printed circuit boards conformal coated, it’s Suitable for operation with average Annual Relative humidity up to 90% and altitude of up to 2,200m. If the meter is reasonably and safely installed and used according to the guideline, its lifespan will be extended. This product could only be used within its provisions; SHENZHEN HEXCELL ELECTRONICS TECHNOLOGY.,LTD. has no responsibility for the damage and personal injury caused by faulty operations, operation and the usage beyond the specific range.
Safety Information
In each chapter of this manual, different letter symbols and graphic symbols which are adopted to express the danger according to different levels of danger will be explained. Please pay attention!
This sign is to remind of possible danger, which will possibly cause some severe hurt and damage to people and the equipment.
This sign is to remind of possible unexpected situation, which might result in personal injury, equipment damage and data error.
Safety Rules
1)Pay attention to this product’s rated voltage and maximum current.
2)Pay attention to this product’s measured load capacity.
3)Correct and reliable installation and connection.
4)Pay attention to effective cross-sectional area of wire connection.
5)Do not touch bare wire or use bare wire to connect.
6)Please don’t use this product in explosive environment.
7)Pay attention to meter’s seal management.
8)Don’t immerse the meter in water and any chemical substance and don’t use any chemical substance to clean the meter.
9)Displays are all examples in this manual, which may have some difference from the real data in meters.
10)Since it is life-threatening to touch live components, the power must be cut off before installation and replacement.
11)Please obey local safety rules; Installation and replacing of meter only could be done by qualified person with specified technology.
12)When installing meter, pay attention to meter’s safety; Appearance damaged or fell downed meters are not allowed to install.
13)Washing the meter by water is not allowed.
14)The Hexcell Standard applies to production and test in Hexcell Electronics, not the standard for client test or acceptance. Only IEC standards apply to the client inspection and acceptance.
Sustainable product improvement is a policy in Shenzhen Hexcell Co. Ltd. Therefore, the company reserves rights to change product operational details and specification. Contents of this manual may be changed without special notification. Without permission in writing from Shenzhen Hexcell electronics Co. Ltd., any part of the manual cannot be reproduced or spreaded in any form or by any means for any purpose by any individuals or other companies
1.Use Instruction
1.1 Overview
1.1.1.Major Application
DDSY1088 Single-phase Keypad Energy Meter takes digital medium as information exchange media. It has a non-volatile memory capable of data storage and with long-term data retention period for a period of not less than 15 years.  It can realize the functions of active & reactive power measuring and pre-payment control. The meter can be used at the point of supply. It is suitable for operation in tropical area.
1.1.2.Main Functions
1)The meter can realize paying first and using later. It adopts STS algorithm (NRS 009-6-7, NRS 009-6-8 and NRS 009-6-9), which has a set of security management system and owns a high level security and is completely compatible with the other STS standard systems.
2)Takes electricity as its electricity billing; Electricity users purchase electricity first, and meter subtracts energy balance. When energy balance is 0 or the overdraft amount allowed by both parties, meter will send power off signal to control load switch automatically cut off. And it will auto restore the power supply after the new purchased power amount is loaded. The load switch meet the IEC 62055-31 requirements.
3)Reverse consumption measured as forward consumption.
4)Measure active and reactive energy. Realizing users’ load detecting and controlling.
1.1.3.Additional Functions
1)Recording event of Terminal cover open,  Meter cover open and power off events etc. 
2)Detect Meter Box Open. Once the meter box is open, the meter will trip and record this event.
3)The meters can detect the presence of strong magnetic fields and give out alarm(s) against the same. 
1.1.4.Normative References
1)IEC62052-11 Electricity metering equipment (A.C)-General requirements tests and test conditions- Part11: Metering equipment. 
2)IEC62053-21 Electricity metering equipment (A.C)-Particular requirements-Part21: Static meters for active energy (classes 1 and 2).
3)IEC62055-31 Electricity metering -Payment systems-Part31:Particular requirements Static payment meters for active energy(class 1 and 2) 
4)IEC62055-41 Electricity metering-Payment systems-Part 41:Standard transfer specification (STS) - Application layer protocol for one - way token carrier systems
5)IEC62055-51 Electricity metering -Payment systems-Part51:Standard transfer specification(STS)-Physical layer protocol for one-way numeric and magnetic card token carriers
1.2 Technical Parameters
1.2.1Meter Operating Voltage
1)Meter rated voltage Un                            230V
Meter operating voltage range                    130V~265V
2)Limit range of operating voltage:             0Un~190%Un 
Within this range, the meter will show no damage; it will indicate normally, but it’s not guaranteed that the accuracy class as well as load control equipment’s normal operation. After operating voltage turn to normal again, meter will work normally and its metering accuracy class will remain unchanged.  
1.2.2 Meter current parameters
1)Imax                                                         60A
2)Meter starting current (0.4%Ib)               40mA
3)Meter metering current range                   40mA ~60A
4)Common current specification                   10(60)A
1.2.3 Meter frequency parameters
1)Rated frequency fn                                   50Hz
2)Frequency application range                     95% fn~105% fn
1.2.4 Self- power consumption of meter
1)Power consumption of voltage circuit        ≤1.5W  8VA
2)Power consumption of current circuit        ≤6VA
1.2.5 Meter active metering accuracy
DDSY1088’s active measurement accuracy conforms to IEC62053-21 class 1.
DDSY1088 --- Active power class 1 percentage error limit.
Table 1 1: Meter active metering accuracy
1.2.6 Display Mode
The meter displays numeric.
1)Display mode                                                    LCD display with backlight 
2)Character digits for data item display                8 digits including 6 integers and 2 decimal
3)Character digits for data ID display                    2 digits
1.2.7 Meter Pulse Constant
1)Active pulse constant                       1000imp/kWh
2)Reactive pulse constant                   1000imp/kWh
1.2.8 Meter Active Check Output
The meter is equipped with special pulse indicator for testing active energy (LED is on the nameplate of meter). In order to ensure the accuracy of active measuring test, according to different current test points, pulse quantity collected from test should be incremented with the increase of current, and reasonably select pulses between the numbers 1~8. 
1.2.9 Meter Serial Communication IntePLCace
IntePLCace 1:
1)Type                     Serial bi-direction communication intePLCace
2)Baud rate              4800bps
3)Application            Measuring data reading and related data item configuration
4)Pattern Non-modulated IR communication
IntePLCace 2:
1)Type                      PLC communication intePLCace
2)Baud rate               9600bps
3)Pattern                   PLC communication
IntePLCace 3:
1)Type                      Virtual Token Carrier port
2)Baud rate               300-4800bps
3)Application             Retrieve recorded meter data
1.2.10 Meter EMC

Table 1 2: EMC
1.2.11 Meter application environment
Table 1 3: Application environment
1.2.12 Meter insulation test

Table 1 4: Insulation test
1.3 Meter Operating Principle Diagram
This METER circuit consists of measurement and control circuit modules centralized with SOC single chip (with internal measurement module, real-time clock and temperature testing compensation circuit etc.), memory circuit module composed of memory chip, PLC module, power supply circuit module, cover open detection module, LCD display, audio reminding user information display module, IR emission and IR receiving circuit module etc. the current sampling uses measurement method of CT sampling, while voltage sampling uses dividing resistance network, and meter adjustment is completed via software.
2.Physical Design
2.1Meter Construction Diagram
METER  diagram:

2.2 Meter Dimension Diagram
METER dimension diagram:
Outline dimension: 202mm×112mm×73mm
Meter Box diagram:
2.3 Meter Wiring Diagram
All terminals of meter locate in the terminal cover with secured screws fitted with user seal to prevent from operations such as unauthorized connection or other settings, etc.
2.4 Meter Protective Class
The meter protection class is Class II, double insulated. The test is carried out with the keypad energy meter produced by SHENZHEN HEXCELL ELECTRONICS TECHNOLOGY.,LTD in accordance with IEC60529-4. METER is sealed to prevent access to the meter. The METER test results are shown as follows: IP 54. 
2.5 Resistance to Heat and Fire
Resistance to heat and fire class: V0 (all the casing made out of heat-resistant and fire-retardant material).Temperature rise at any point of the external suPLCace of the meter not exceed by more than 20K with an ambient temperature at 45℃。
3. Meter Function Lists
3.1 Active Energy Metering
3.1.1 Respectively measured forward active power and reverse active power, reactive power;
3.1.2 Measure total active and reactive energy: Electricity quantity continuously increase even under reverse current(reverse + forward direction).
3.1.3 Measure apparent electric energy;
3.1.4 Measure 4 tariff power: respectively measure T1/T2/T3/T4 total active and reactive electric energy, forward and reverse active and reactive electric energy
3.1.5 Measure 4 tariff apparent electric energy.
3.1.6 Save power data up to 12 months 
3.1.7 Prepayment charge function.
Hexcell DDSY1088 single phase split type repayment STS meter owns the measuring function of forward and reverse direction active electricity energy, has impulse light and impulse terminals output. DDSY1088 meter can detect the real-time usage condition.
Separately record the balance and total electricity quantity, Check current total electricity quantity with STS standard testing command (refer to 3.2).When balance electricity down to 0,the relay automatically switch off, and won’t automatically connecting until new electricity quantity recharged.
DDSY1088 can measure reverse power in the same way of measuring forward power and the energy can be accumulated in total active energy and active energy of each settlement month. It also has impulse LED and output terminal to detect the status of meter.
Meter will record balance and accumulated kWh respectively. To inquiry the accumulated kWh, users just need to input the STS standard testing token. When the balance is 0, meter will automatically trip. And only after recharge the meter, the relay will automatically back on.
3.2 Recharging Function
The METER is preloaded with 50 kWh. If customers buy the token from POS, input the 20 digits STS standard encrypted token, the meter will automatically recharge the relevant kWh, and on meter LCD display “ACCEPT”.
When the inputted kWh and the balance in the meter is more than 999999.99kWh, the meter will automatically reject recharge. But this token can be reused when the balance is less than the maximum energy. 
Meter will automatically verify if the TOKEN has been used or not. Meter will automatically verify the TOKEN time and recode the last 50 times used TOKEN. If the lastest inputted TOKEN time is earlier than the previous 50 times TOKEN, meter will REJECT this token. In this case pls consult the TOKEN vending point.
3.3 Tampering Alarm Function
Under the condition of cover opening and current reverse, meter will alarm. The alarm won’t disappear even the tampering is finished when opening meter cover and terminal cover. This status can only be removed by TAMPER TOKEN. On Repair Column, Token means only after input token can clear the icon. Repair means after the tamper even ended, the icon will disappear.
3.4 Demand measure
1)Measure total active demand and 4 tariff demand;
2)Save demand value and demand occurrence time of last 12 months;
3)Demand period can be set via PC。
3.5 Instantaneous value measurement
6)Active power(kW)
7)Reactive power(kvar)
8)Apparent power(kVA)
9)Power factor
10)Grid frequency(Hz)
3.6 Tariff and time frame list Function
11)Automatically switchover calendar and leap year etc
12)Total 4 tariff
13)Time frame list of ordinary day: Divided to 7 time frame lists, from Monday to Sunday, the meter automatically switchover the time frame list according to the current day.
Set via PC software, format below:
NNXXXX*8,Total 8 time frame,NN-tariff number, XXXX-switching time of tariff
Time frame that no need to set is 000000。
e.g.:010600, 021200, 031500,042000,000000,000000,000000,000000
Represent:06:00~11:59  Tariff T1
                  12:00~14:59  Tariff T2
                  15:00~19:59  Tariff T3
                  20:00~05:59  Tariff T4
14)Time frame list in Holiday:Total 16 time frame lists,meter automatically switchover the holiday time frame list according to the current holiday .
Set via PC software, format below:
MMDD+ NNXXXX*8,MMDD-Month, Day of corresponding holiday, Regarding other setting, please refer to time frame list of ordinary day. 
15)Time frame list in Special holiday:Total 16 time frame lists,meter automatically switchover the special holiday time frame list according to the pre-set special holiday. 
Set via PC software, format below:
YYMMDD+ NNXXXX*8,YYMMDD- Month, Day of corresponding holiday, Regarding other setting, please refer to time frame list of ordinary day. 
Priority:special holiday>Normal holiday>Ordinary Day 
3.7 Meter data inquiry
Three ways of data inquiry:
a)Reading via PC software
b)Reading via keypad display command
c)Reading via HHU
Please refer to keypad display。
3.8 Power-off Trip Function
When meter detect power off, it will automatically trip, when the power goes back to normal, meter will automatically restore to the previous relay status.
3.9 Over Power alarm function
When the power exceed the threshold, meter will enter into the over power status and display “OUE_LOAD”. Only after the power is less than threshold, this message will disappear. Input 47 to display the current power, input 07 to display the threshold of meter. The threshold can be settled by STS token.
In addition, the meter has the below over power function:
1.When the power exceeds the settled threshold 10 seconds, meter will enter into Over power status.
2.If over power existing more than 45 seconds, meter will automatically trip and after 150 seconds relay will automatically back on.
3.If the meter enters into over power status more than 5 times, meter will display ‘5OUE_LOAD’ and then after the 5th trip, the relay will back on after 30 minutes.
3.10Clear balance Function
By using STS token, the total balance in the meter will be cleared to 0 and the meter will trip immediately. Meter will display “ACCEPT”
3.11 Changing KEY Function
The meter KEY can be changed by STS token. The rules of changing key comply with IEC 62055-41 standards. Firstly, please refer to the below table to confirm if the different level of key can be changed or not.
3.12Data record Function
Meter can record the charging and tampering information, please use the PC software to read the data by optical head.
3.13Prepayment operation instruction
The Power Sales Management System will produce a 20 digits code (generated based on user’s information and purchase amount). After the user input this code via the meter’s keypad, meter will decrypt the code. After passing the encryption authentification, current purchase amount will be written into meter’s memory and added to the energy balance and stored; When abnormal consumption happens, the abnormal consumption amount will be deducted from the purchase amount and the new energy balance will be stored in memory; When the user is consuming power, the meter will deduct the energy balance gradually according to corresponding conditions. When the power-off condition is met, meter will cut off power supply and when power supply condition is met, meter will connect to user load automatically.
1)Open an Account
Opening an account is necessary after the key system of meter is changed and user information registration is completed. Opening an account can give user a number and appointed ID in order to correspond one meter with one user. At the same time, initial purchasing power, the key and other parameters can also be written into meter.
2)Purchase Power
When the energy balance in meter is insufficient, the customer can visit the power vending office to purchase electricity. At vending office a 20 digits serial number (TOKEN) including the kWh information will be produced based on user information and purchase amount. After obtaining the 20-digits token, load it into the CIU. The CIU will increment the purchased kWh into the balance but will not loss any existing credit balance. Upon acceptance of a valid token credit the exact amount contained on the token to the appropriate register in the meterand shall increment the register by this amount.
Power purchase method:
(1)Visit the local power vending office.
(2)Provide your meter ID to the operator.
(3)Inform the operator the amount you want to buy and pay the bill.
(4)Obtain a 20-digits token printed on your receipt.
3)Load power
User will input the 20-digits serial number via meter’s keypad. After passing key authentification, meter will accept purchase amount and adjust the energy balance and cumulative purchase amount and then save the new energy balance in EEPROM. At the same time power amount loaded this time will also be displayed on LCD. 
(1)Key in the 20-digits token via keypad.
(2)Confirm the numbers on LCD.
(3)If token is wrongly input, please use backspace to modify.
(4)After inputting all the 20 digits, push Enter to confirm the token input.
(5)If token is correctly input, LCD will display “accept” and the power amount purchased.
If token is wrongly input, LCD will display “reject”. User can press the “Sequence-Backspace” button to delete the wrong digit.
3.14LCD Display
3.14.1Display (CIU)
When meter is energized, the LCD will initialized and display all contents. After 4 seconds, LCD will display the seted parameter. 

When there is tampering, over power and meter error, meter will automatically switch to the below display
3.14.2 Scroll Display (CIU)
If there is no operation, meter will display: Balance
3.14.3 Short Code Display (CIU)
Short Code List

3.15Indicator Status
1)METER indicator state:
a)Pulse indicator: red, blinks during power consumption.
b)Credit indicator: When below threshold 5kWh, it will blink in red and the buzzer will alarm. When the balance is 0, the red LED will keep on lighting.
c)Tamper indicator: when the LED is red, it means tamper events occured.
3.18 User Card
The METER is supplied together with a plastic card of dimension 85mm X 54 mm indicating the meter number on the face side.
4.Meter Installation Instruction
5.1Cautions on Operation
The METER of BS5685 mounting.The installation and commission operator of energy meter must be technically qualified as below: 
1)Trained with relevant technical training.
2)Be familiar with and comply with safety regulations, strictly comply with specific regulation of safety.
3)Please see if the required materials and tools are all prepared before starting operation (see 5.2 “Tools and Materials required”).
5.2Tools and Materials Required
The following tools and materials are necessary for installing the meter:
1)The energy meter preset correctly (already opened an account) and sealed well.
2)Customers’ information chart of energy meter.
3)Screws to fix energy meter.
4)Seal and seal tools provided by the Utility.
5)Slotted screwdriver and cross screwdriver which are used to secure screw.
6)Drilling tools (if it is needed) and multi-meter.
5.3Installation Dimension Figure
METER installation dimension figure:
Installation dimension 
height 140mm  width 100mm
Meter Box installation dimension figure:
Installation dimension: 210x110mm
5.4Cautions on Installation
1)Before wiring, please carefully check the connection diagram on meter case and confirm the phase line, and neutral line (ground wire) consistent with connection diagram. It is better to use copper wire and copper contact to connect to meter.
2)If the cable is old, operator shall cut the end of cable to ensure the new exposed wire end is about 15mm long to be used to connect; if cable diameter is between 3mm and 6.5mm, directly connect to inside of terminal and make sure it secured; if cable diameter is less than 3mm, then it is necessary to use a suitable size copper or aluminum bushing to clamp cable end so as to avoid loose contact of connection resulting in terminal burnout.
3)During wire-connection, firstly loosen each screw on each terminal, then insert In-phase line into end of connection aperture and the in-neutral line into end of connection aperture, fully tighten screws of terminals. Similarly insert Out-phase line into end of connection aperture. Tighten screws of terminals fully and make them secured.
4)Power on energy meter to test the working condition, if energy meter works normally, record readings of meter. Otherwise, please carefully test condition of installation and connection and working voltage.
5)Be gentle with the energy meter so as to avoid dropping and collision during whole installation processes.
6)When installing energy meter, please be careful with operation and power usage safety so as to avoid accident.
5.Transport and Storage
1)The product shall be transported and stored according to the related rules. No intense impact to the product is allowable during transportation and unpacking.
2)The product shall be stored in a clean place where the ventilation is good, the ambient temperature is -25℃~70℃, and the relative humidity is not more than 75%, and make sure no corrosive gas or harmful material present and the natural ventilation is good.
3)The product shall be stored on shelf in a warehouse and the stacking height shall not be more than 8 layers.
The manufacturer warrants its products against defective parts and workmanship and will repair or (at its option) replace, free of charge, any meter which is or may become defective under proper operation with all seals in good condition within the warranty period specified in contract from date of sales.
The meter features self-test. If the following information is found on the LCD, or the self-test information displayed on LCD is abnormal (e.g. character missing or character incomplete etc.), contact the manufacturer for advice.
SHENZHEN HEXCELL ELECTRONICS TECHNOLOGY CO., LTD. guarantees to provide a lifetime service with the meters and the related devices made in our company. In product distribution areas, there are offices and or agents accompanying with customer service center responsible for providing customers with product consultation and maintenance service etc..
Tel: 0086-755-26622430
Fax: 0086-755-26621430
Add: 1-6# Bldg., Tongfuyu Industrial Zone, Aiqun Road, Shiyan Town, Bao’an District, Shenzhen, China 
Zip code: 518108