DTZY315-G Three phase Four wire Cost Control Smart Meter (4G/NB-IOT State Grid Standard)

1. Overall performance

1.1 The design of the electric energy meter circuit and the selection of components are based on a large environmental tolerance, thus ensuring long-term stable operation of the entire machine. The accuracy is basically not affected by frequency, temperature, and voltage changes. The whole machine has a small volume, light weight, good sealing performance, and significantly improved reliability.

1.2 Users can remotely manage their electricity consumption by remotely controlling the opening and closing of the electricity meter and setting parameters such as time periods.

1.3 When the power supply loses power, the lithium battery serves as a backup power source to ensure that internal data is not lost, the calendar, clock, and time period program control functions operate normally, and automatically put into operation when the power is restored. There is a photoelectric coupling pulse output interface set on the terminal box of the electric energy meter for error testing and data acquisition. The pulse output constant is consistent with the meter constant marked on the label.

1.4 The operation information of the electricity meter can be transmitted through two media: handheld computer and RS485 interface. The power department can choose one or more transmission methods according to the specific situation in the local area The communication protocol of the electric energy meter complies with DL/T645.

2. Measurement function

2.1 Time sharing metering function

Accumulate and store total, peak, off peak, flat, and valley active and reactive energy according to the corresponding time periods; Measure the positive and negative active and reactive phase separated electrical energy separately.

2.2 Maximum demand measurement function

2.2.1 The maximum positive and negative reactive power demand and its occurrence time for the total and each rate;

2.2.2 All required data can be stored for the current and last 12 months, displaying current and last month's data.

2.2.3 The display and recording of demand shall have 2 integers and 4 decimals; The unit of maximum demand for active power is kW, and the unit of maximum demand for reactive power is KVAR. The record of the occurrence time of maximum demand is month, day, hour, minute, and second.

3. Electrical parameter measurement function

4. Main functions

4.1 Alarm function

When the energy meter experiences alarm events such as voltage loss, current loss, reverse phase sequence, overload, reverse power, battery undervoltage, or receives remote alarm commands, the red alarm light of the energy meter remains on, the buzzer intermittently alarms, and the meter outputs an alarm relay signal. When the buzzer alarms, it can be turned off by pressing the button. When the event returns to normal, all alarm signals will be automatically removed.

4.2 Power outage control

When the electric energy meter receives the opening and closing instructions issued by the remote electricity sales system, it automatically cuts off the user's load or restores the user's power supply after strict password verification and security authentication.

4.3. Open lid alarm

When the electric energy meter is powered by AC, if the top cover is opened, it will automatically record the start and end times of ten times the cover is opened.

4.4 Power down storage

After a power outage, the electricity meter automatically enters a waiting state to ensure that the clock and centennial calendar are not affected by the power outage. Non volatile memory can permanently store data, ensuring that in the event of battery failure, all operational information of the electricity meter from yesterday and all information from the previous month will be permanently saved. Ensure that any accidents occur with the electricity meter and that data is not lost. During the automatic meter reading period, if there is a power outage, the energy meter will automatically read again after being powered on.

4.5 Time period control

The electricity meter can have multiple sets of rate periods, and each rate period can be set with multiple time zones throughout the year. Each time zone is set with 14 daily time periods and 4 rates (peak, off peak, off peak, and off peak) for 24 hours. The electricity meter has a set of backup periods, and the activation time of the backup period can be pre-set. After the electricity meter runs for the set time, it automatically replaces the original period. Under strict password verification and security authentication, parameters such as the tariff period table in the energy meter can be remotely set.

4.6. Automatic settlement function

4.6.1 When the electricity meter reaches the preset "end of month settlement date", the meter automatically transfers the data of electricity energy, demand, voltage qualification rate, etc. at that time to the data of the previous month, and at the same time resets the current maximum demand data to zero. The data of the previous month is transferred to the data of the previous month, and so on. The electricity meter can store 12 months of historical electricity consumption. The 'month' here is divided according to the 'end of month settlement date hour'.

4.6.2 "Month end settlement date" can be set to any hour from the 1st to the 28th, and defaults to "0:00 on the 1st". If the 'settlement date' is greater than 28 days or 0 days, it is considered not to be automatically settled.

4.6.3 In addition to the "end of month settlement date hour", the electricity meter can also set multiple "settlement date hours" according to user requirements. When the electricity meter runs to the "settlement date hour", it automatically freezes the energy, demand and other data at that time. This data can be read through RS485, infrared, photoelectric or other communication interfaces, and automatically covers when running to the next natural month.

4.6.4 The historical data of the past 12 months can be read through any communication port, and the historical data of the past 2 months can be read by viewing the LCD display.

4.7 Data Freeze Function

4.7.1 The broadcast data of the electricity meter can be frozen through the communication port. The freezing of broadcast materials can be divided into timed freezing, instantaneous freezing, agreed freezing, and daily freezing. The frozen content and data identifiers should comply with the requirements of DL/T 645-2007 and its filing documents. The frozen data can be read through RS485 or infrared communication port.

4.7.2 Timed Freezing: Freeze electrical energy data at specified times and intervals, with each frozen amount saved at least 12 times.

4.7.3 Instant Freeze: Under abnormal circumstances, freeze all current electricity data, calendar and time, as well as important measurement data. Instantaneous freezing saves the last 3 data.

4.7.4 Agreed Freeze: Freeze the electrical energy and other important data at the agreed time when converting between new and old rates/time periods or when the power company deems there to be special requirements

4.7.5 day freeze: stores the daily electricity at midnight and can store data for 2 months.

4.8 Event recording function

4.8.1 The electricity meter has the following function of recording the last 10 events, and can also increase the types and frequency of event records according to user requirements. Event records can be read through any communication interface for analyzing abnormal operation of the electricity meter.

4.8.2 Record the total number of programming attempts, the time of the last 10 programming attempts, operator code, and data identification of programming items.

4.8.3 Record the total number of times the demand is reset, the time of the last 10 demand resets, and the operator code.

4.8.4 Record the total number of time calibrations (excluding broadcast time calibrations), the time of the last 10 time calibrations, and the operator code.

4.8.5 Record the total number of voltage losses for each phase, including the time of the last 10 voltage losses, the end time, and the corresponding electrical energy data.

4.8.6 Record the total number of phase breaks for each phase, the time of the last 10 phase breaks, the end time, and the corresponding electrical energy data.

4.8.7 Record the total number of current losses for each phase, the time of the last 10 current losses, the end time, and the corresponding electrical energy data.

4.8.9 Record the last 10 occurrences, end times, and corresponding electrical energy data of current imbalance.

4.8.10 Record the total number of times the voltage (current) reverse phase sequence has occurred, the time of the last 10 occurrences, the time of the end, and the corresponding energy value data.

4.8.11 Record the total number of times the meter cover has been opened, as well as the occurrence and end times of the last 10 meter cover opening events.

4.8.12 Record the total number of start button cover events, including the occurrence and end time of the last 10 start button cover events.

4.8.13 Permanently record the time of occurrence of the reset event on the energy meter and the energy data at the time of reset.

4.8.14 Record the total number and duration of overloads for each phase, as well as the duration of the last 10 overloads.

4.8.15 Record the total number of power outages, as well as the time of the last 10 power outages occurring and ending.

4.8.16 Record the total number of total voltage losses, the time of the last 10 total voltage losses, the end time, and the corresponding current value.

4.8.17 can read the total number of occurrences and/or cumulative time of each event record.

4.9 Communication function

4.9.1 Communication Interface and Protocol

4.9.1.1 The electricity meter has 2 fully isolated RS485 communication interfaces (according to user requirements) and 1 modulated infrared communication interface. The communication circuits are independent of each other, and the damage of one channel does not affect the normal operation of other channels.

4.9.1.2 The baud rate for RS485 communication can be set within the range of 1200-9600bps, while the default baud rate for infrared communication is 1200bps.

4.9.1.3 Communication protocols can also be embedded with other communication protocols according to user requirements, while meeting DL/645-2007 requirements.

4.9.1.4 The RS485 communication interface is connected to the internal circuit of the electric meter through optocouplers, and is designed to withstand lightning strikes and overvoltage. It can withstand AC 380V for 2 minutes without damage.

4.10 Programming Permissions and Limitations

When programming an electric energy meter through a communication interface, it is important to note that in order to protect the reliability of internal data, the meter is equipped with dual protection measures of a programming switch and a programming password to prevent unauthorized individuals from performing programming operations.

4.11 Software and hardware protection

4.11.1 Hardware protection adopts a button form, set under the sealable nameplate cover, and the button can only be accessed by opening the nameplate cover. The programming switch can switch the programming allowed and disabled states of the energy meter, and the hardware programming switch is the "programming" button. The "Programming" button is located under the side flip cover at the bottom of the meter panel, which can be lead sealed to prevent unauthorized personnel from operating. When the "Program" button is pressed and the "" symbol (hardware unlock indicator) is displayed below the meter LCD, it indicates that the hardware unlock is successful, and the meter is in the "Program Allow" state. If the energy meter suspends operation for more than 240 minutes in the allowed programming state, the meter will automatically lock and the "hardware unlock indicator" will disappear. When in the "programming allowed" state, various programming operations on the electricity meter can be allowed; When in the "non programming allowed" state, all programming operations are prohibited except for broadcasting timing within 5 minutes per day and reading meters, which are not controlled by the programming switch.

4.11.2 There are two types of software protection passwords for energy meters: administrator password and operator password. According to DL/T 645-2007, the administrator password is level 02 and the operator password is level 04. The initial factory setting for administrator level 02 password is "000000", and the initial factory setting for operator level 04 password is "111111". When programming the electric energy meter, the programming switch must be pressed first, and the programming password must be entered correctly before entering the programming mode and allowing programming. If the programming password is entered incorrectly three times in a row, the energy meter will automatically lock the programming function for 24 hours.