The Landis+Gyr E650 (ZMD/ZFD) and E850 (ZxQ series) and the Elster A1800 ALPHA, now sold by Honeywell, are three-phase electronic energy meters for commercial boundaries, substations, generation plants and industry. They measure active and reactive energy in four quadrants with accuracy classes from 0.2S to 1, store load profiles and events, and are read remotely through optical ports, serial ports and communication modules.
What they are and where they are used
The Landis+Gyr E650 (known by its ZMD code), Landis+Gyr E850 (ZxQ series, which includes the ZMQ code) and Elster A1800 ALPHA are three-phase electronic energy meters. They are used at points where the measurement has commercial value: boundaries between the utility and a customer, generation plant outputs, transmission substations and large industrial consumers. They are commonly called revenue meters or billing meters.
Landis+Gyr is a Swiss meter manufacturer. The Elster brand now belongs to Honeywell, which sells the A1800 ALPHA in its commercial and industrial meter line.
A revenue meter does not work alone: it measures through metering-class current transformers and voltage transformers, and the whole set (transformers, wiring and meter) is what determines whether the measurement is correct. How the metering system is organized is covered in the guide on commercial boundary and metering system.
Variants: E650 ZMD, E850 ZxQ, A1800 ALPHA and A3 ALPHA
| Model | Application | Main difference |
|---|---|---|
| Landis+Gyr E650 (ZMD402, ZFD402) | Industry, commerce and smart grids | Modular; classes 0.2S, 0.5S and 1 (IEC) or C and B (MID); direct or transformer-connected |
| Landis+Gyr E850 (ZxQ series, ZMQ) | Power stations, wind farms, transmission, substations and large industry | High accuracy, class 0.2S or 0.5S for active energy; wall-mount (f6) or rack (f9) version |
| Elster A1800 ALPHA (Honeywell) | Commercial, industrial and substation metering | Four quadrants, time-of-use tariffs, two communication ports |
| Elster A3 ALPHA / A1700 | Polyphase metering in ANSI or IEC markets | Earlier generations and close lines of the same ALPHA family |
The letter in the Landis+Gyr code indicates the connection and measurement type; the exact code of an installed unit is confirmed on its nameplate and in the manufacturer’s ordering documentation.
Main characteristics
- Four-quadrant measurement. Active, reactive and apparent energy in both directions, needed when there is generation or self-generation at the metering point.
- Accuracy classes. Landis+Gyr publishes 0.2S, 0.5S and 1 for the E650 and 0.2S or 0.5S for active energy for the E850. The class required at a boundary depends on the country’s regulation and on the energy passing through the point; the class of the instrument transformer must be consistent with that of the meter.
- Load profiles and events. The E650 stores two load profiles and up to one thousand events, with calendar and tariff control. The A1800 ALPHA includes time-of-use metering.
- Revenue protection functions. Elster introduced the A1800 with revenue protection functions, aimed at detecting tampering and connection anomalies.
They are not power quality analyzers: if the problem is harmonics or dips, what is needed is a Class A instrument; see power quality analyzer.
Landis+Gyr E850 ZMQ200: what the manufacturer’s brochure publishes
The E850 ZMQ200 brochure (document D000011399, edition k, September 2017, in English) presents it as Landis+Gyr’s high-accuracy meter for network metering: generation, transmission, substations and large consumers connected to the grid. Data from the brochure:
- Accuracy classes: 0.2S or 0.5S for active energy and 0.5 or 1 for reactive. The nominal current of 1 A or 5 A is set by parameterization in the class 0.2S version.
- Mounting: wall-mount (f6) and rack (f9) version with Essailec connector.
- Registers: two independent profiles, 8 Mbyte memory for profiles and statuses, 8, 16 or 36 measurement channels with total registers, 24 energy registers for tariffs, 41 diagnostic registers, event log and monthly and daily index profiles.
- Voltage quality: voltage dips (dip table) and total harmonic distortion (THD), plus instantaneous values of voltage, current, phase angle, power factor per phase and frequency. It does not replace a Class A power quality analyzer.
- Monitoring functions: alarm indication with contact, indication of phase failure and of current without voltage in individual phases, self-diagnosis and periodic test of all memories, and compensation of current and voltage transformer errors.
- Power supply: three-phase from the voltage measurement circuit and an additional supply, with a special operating mode for lightly loaded instrument transformer lines and for remote reading when voltage is missing in the measurement circuit.
- Communications: up to eight output contacts, three independent communication channels and the DLMS protocol, with an optical interface per IEC 62056 and an integrated RS-485 interface. Combined with the Q22 communication unit it gives three independent channels with RS-485 and allows three reading centers to access the meter at once. There are also modules for RS-232, Ethernet TCP/IP and GSM/GPRS or UMTS.
- Software tools: MAP 110 (installation support, meter reading, load profile analysis, dip table display and communication settings) and MAP 120 (parameterization file database for an engineering department). The brochure does not state the version.
This brochure describes a single model. For the E650 and the A1800 ALPHA, the exact figures for channels and profiles depend on the series and the firmware, and must be taken from the technical document of the installed meter; that is why they are not given here.
Communications and integration
- Landis+Gyr: the E650 is read over the IEC or DLMS protocol through optical and electrical interfaces, or through the pluggable E65C modules (including cellular LTE versions), which are also compatible with the E850.
- Elster A1800: two independently readable ports (the second optional), with RS-232, RS-485, modems and cellular connectivity, and an open protocol for integration into reading systems.
- Telemetering and SCADA: the billing reading goes to the meter data management system; if the variables are also wanted in the substation or plant SCADA, they are integrated through a gateway or RTU.
Frequently asked technical questions
- Elster A1800 manual in PDF: Honeywell publishes datasheets and manuals on its product page, some in several languages and others requiring registration.
- Configuration software: each manufacturer has its own reading and parameterization tool; the version must match the meter model and firmware.
- Negative energy or swapped quadrants: it is usually polarity or sequence in the current and voltage wiring, not a meter fault.
- Differences between the main and the backup meter: they often come from the instrument transformers or the burden on the secondaries.
- Remote reading that drops: the problem is usually in the communication module, cellular coverage or channel configuration.
How we help
We do the configuration of the device and its communication remotely, worldwide, through remote configuration. At Tiza Group we integrate revenue meters into the control and communications system of the substation or plant, and review the metering wiring when the figures do not add up; see control, protection and communications configuration. Testing of the instrument transformers that feed the meter is covered in current and voltage transformer testing, in Colombia or elsewhere on request. To get a quotation, write to us through contact.
Related guides
- Commercial boundary and metering system
- Energy meter and multifunction meter
- Schneider ION9000 meter
- Siemens SENTRON PAC meters
- Current transformer
- Substation RTU and gateway
- SEL-735 and SEL-734 meter
- GE EPM 6000, EPM 7000, Shark 200 and Nexus 1500 meters
- Fluke 435-II, 1760, Hioki PQ3198 and PQ3100 network analyzers
References
- Landis+Gyr, E650 and E850 (ZxQ) product pages and E650 Series 4 datasheet.
- Landis+Gyr, E850 ZMQ200 brochure, document D000011399 k (09-2017).
- Honeywell, A1800 ALPHA product page.
- IEC 62053-22, static meters for active energy, classes 0.1S, 0.2S and 0.5S.
- IEC 62056 (series), electricity metering data exchange (DLMS/COSEM).
Frequently asked questions
What is the Landis+Gyr E650 ZMD meter?
It is Landis+Gyr's modular industrial and commercial meter, for direct connection or through current and voltage transformers. The ZMD402 designation corresponds to variants of the E650 Series 4. Landis+Gyr offers it in classes 0.2S, 0.5S and 1 per IEC, with two load profiles, event log and E65C communication modules.
Where can I find the Elster A1800 technical manual?
The A1800 ALPHA is now sold by Honeywell, which publishes the datasheet, manuals and certificates on its product page, some requiring prior registration. Before using a manual, confirm that it matches the hardware and firmware version of the installed meter.
What is the difference between the Landis+Gyr E850 and the E650?
They are two different lines from the same manufacturer. The E850 (ZxQ series) is Landis+Gyr's high-accuracy meter for power stations, wind farms, transmission and substations, in wall-mount or rack versions. The E650 is the modular meter for industry and commerce. The choice is set by the metering point and the class required by the applicable regulation.