SATEC EM133

Compatibility

Compatible with EpiSensor Edge over Modbus RTU or Modbus TCP

The EM133 is compatible with EpiSensor Edge over Modbus RTU on its built-in COM1 RS-485 port, read through a ZMB-31 Modbus Interface or a Gateway serial port, and over Modbus TCP on port 502 when the Ethernet module is fitted. SATEC publishes the register map with decimal addresses, data types, low-word-first word order, units and worked conversions.

EM133, EM133-XM and EM133-MID with any current input, using the EM133 Modbus reference guide BG0530 Rev. A4 with manual BG0491 Rev. A15. Site check: read the device resolution at register 2390 and the energy decimal places at register 2393, then compare the first voltage read with the display. The EM133-R and EM133-XM-AR residential versions, DNP3, IEC 60870-5, PROFIBUS, CANopen and SATEC ASCII are outside this guide. Read-only monitoring: no writes to setup, password, relay or reset registers.

Connect it with

• Modbus Interface ZMB-3X From €399 ex VAT Configure
• Gateway ZGW-20 From €899 ex VAT Configure
• Evaluation Gateway on a Raspberry Pi Edge with one device licensed Free Set up

Models

Specifications

The EM133 is a three-phase multifunction and time-of-use energy meter for DIN-rail mounting, with a 2 × 16 character backlit LCD, an anti-tamper enclosure and an embedded controller with 16 setpoints. It measures true RMS voltage, current, power, power factor, neutral current, unbalance and frequency at 25, 50, 60 or 400 Hz, four-quadrant energy, and harmonics to the 40th order. One expansion module can be fitted: digital inputs and relays, analog outputs, or a second communication port.^2, 3

Models

EM133 standard; EM133-XM extended memory, over 40 times the standard capacity, with an internal temperature sensor and three data recorders; EM133-MID, MID certified (5 A).³

Order string

Current input (5, 1, 63, 100, RS5, HACS, HACS-SPDR), calibration frequency (25HZ, 50HZ, 60HZ, 400HZ), resolution (blank low 1 A and 1 V, H high 0.01 A and 0.1 V), power supply (ACDC 40 to 300 V AC/DC, SE self-energised, 21DC 12/24 V DC), then seal, protocol and test options.³

Inputs

Voltage up to 690 V AC line-to-line direct, measurement range 15 to 480/828 V AC (L-N/L-L). Current through 5 A CTs (In 5 A, Imax 10 A) or 1 A CTs (In 1 A, Imax 2 A), direct 63 A, the RS5 split-core input or SATEC HACS sensors.^2, 3

Accuracy

Active energy class 0.5S to IEC 62053-22 and IEC 60688, ANSI C12.20 class 0.5, and EN 50470-3 class B or C on the 5 A version. Optional calibration to class 0.2/0.2S.³

COM1

Built-in two-wire RS-485, 3000 V AC optical isolation, up to 115.2 kbit/s and 1000 m. Factory settings: Modbus RTU, address 1, 19,200 bit/s, 8 data bits, no parity, 5 ms response delay.^2, 3

Ethernet (COM2 module)

Transformer-isolated 10/100BaseT on RJ45. Modbus TCP on port 502 and DNP3/TCP on port 20000, four connections in total (two Modbus TCP, two DNP3). Factory IP 192.168.0.203, mask 255.255.255.0, gateway 192.168.0.1.^2, 3

Response time

13 ms typical at 9600 bit/s, 11 ms at 19200 bit/s and 9 ms at 57600 or 115200 bit/s.¹

Power supply

ACDC option 40 to 300 V AC 50/60 Hz or 40 to 300 V DC, 5 VA; SE option self-energised from 1, 2 or 3 measured phases, 2 VA per phase; 12/24 V DC option.^2, 3

Mounting

35 mm DIN rail to EN 50022; 125 × 90 × 75 mm; reinforced polycarbonate; IP20.³

Environment

Operating -25 to +60 °C, specified range -20 to +60 °C; storage -30 to +85 °C; damp heat below 95 % non-condensing at +40 °C.²

Interface

Documented measurements and integration boundaries for EM133.

• Addresses are decimal and go on the wire as printed: register 13952 is sent as 36 80. A client that wants Modicon numbers adds 40001, or 400001 above 9999, so 13952 becomes 413953. FC03 and FC04 return the same registers.
• 32-bit values are two registers, low-order word first, with the low word at an even address. They are long integers by default; register 246 can switch analog values, counters and energies to IEEE floats, which are also sent low register first. Read 246 before adding points.
• Units depend on the device resolution at register 2390 (0 low, the default; 1 high, order code H). Low resolution: volts in 1 V, amps in 1 A, power in 1 kW, kvar or kVA. High resolution: 0.1 V and 0.001 kW with a PT ratio of 1 (1 V and 1 kW above it), and 0.01 A.
• 1-second phase voltages V1, V2 and V3 at 13952, 13954 and 13956: UINT32 in volts. They are line-to-neutral in 4LN3, 3LN3 and 3BLN3 wiring and line-to-line otherwise. V12, V23 and V31 at 14012, 14014 and 14016.
• Currents I1, I2 and I3 at 13958, 13960 and 13962: UINT32 in amps. Neutral current at 14466 and frequency at 14468 (UINT32, 0.01 Hz).
• Per-phase kW at 13964, 13966 and 13968 and kvar at 13970, 13972 and 13974: INT32. kVA at 13976 to 13980: UINT32. Power factor L1 to L3 at 13982, 13984 and 13986: INT32, × 0.001. In 3-wire wiring the per-phase power and power factor read zero.
• Totals: kW at 14336 and kvar at 14338 (INT32), kVA at 14340 (UINT32), power factor at 14342 (INT32, × 0.001), kW import at 14348 and kW export at 14350 (UINT32), average current at 14360.
• Energy: kWh import at 14720, kWh export at 14722, kvarh import at 14728, kvarh export at 14730, kVAh total at 14736, kVAh import at 14742 and kVAh export at 14744. UINT32, 0 to 999,999,999. The unit is programmable from 0.0001 to 1 kWh: register 2393 holds the number of decimal places for energy registers (0 to 4, default 4).
• Per-phase kWh import L1 to L3 at 14848, 14850 and 14852 and kWh export L1 to L3 at 14866, 14868 and 14870, when phase energy calculation is enabled at register 2378.
• Voltage THD V1 to V3 at 13988, 13990 and 13992 and current THD I1 to I3 at 13994, 13996 and 13998: UINT32, 0.1 %, 3-second values.
• Registers 256 to 308 are a 16-bit basic set scaled 0 to 9999 between low and high engineering scales, with energies split modulo 10000. Prefer the 32-bit registers, which need no scale arithmetic.
• Identity: serial number at 46080 (UINT32), model ID at 46082, model name at 46084 to 46091 and firmware version at 46100. Wiring mode at 2304, PT ratio at 2305 (× 0.1) and CT primary current at 2306.
• Setup, password (2575), restart (2560), relay control (3244 to 3247), reset and clear registers (3404 to 3414) and the assignable map (0 to 239) accept writes. Keep them out of a monitoring poll.

Setup

1. Identify the meter

   Read the order code from the meter label: current input, calibration frequency, resolution and supply, for example EM133-5A-60HZ-ACDC. Note any module fitted as COM2, and record the wiring mode, PT ratio and CT primary current from the basic settings.

2. Read the port settings

   COM1 is factory set to Modbus RTU, address 1, 19,200 bit/s and 8 data bits with no parity. With an Ethernet module, the Net menu shows the IP address. Enter the same values in the Edge client and leave the meter's settings as they are.

3. Wire the connection

   For RS-485, connect X+, X- and the shield to COM1, give each meter its own address and terminate both ends of the bus. For Modbus TCP, connect the module's RJ45 port to the site network.

4. Make three reads

   Read register 2390 for the device resolution and register 2393 for the energy decimal places, one register each. Then read V1 at 13952 for two registers and decode it low word first, as in the worked read below. Compare the result with the V1 voltage on the display.

5. Add the points you need

   Add currents, powers and the energy counters from 14720, scaled by the decimal places from register 2393. Check register 246 if any value looks like a float, and keep writes out of the polling configuration.

Common questions

What does EM133-5A-60HZ-ACDC mean?

It is an EM133 with the 5 A current input for CT secondaries (In 5 A, Imax 10 A), calibrated at 60 Hz, with the ACDC auxiliary supply of 40 to 300 V AC/DC. The string has no H, so the meter ships with low resolution: volts in 1 V and amps in 1 A over Modbus. Expansion modules are ordered separately, so check the back of the meter: without an Ethernet module, the built-in COM1 RS-485 port is the Modbus route.^2, 3

Why does voltage read 2770 on one meter and 277 on another?

The device resolution setting changes the units. Low resolution, the default, sends volts in 1 V and amps in 1 A; high resolution, order code H, sends 0.1 V and 0.01 A, and 0.001 kW for power when the PT ratio is 1. Read register 2390 (0 low, 1 high) and set the scale in Edge to match.^1, 3

How do I scale the EM133 energy registers?

The 32-bit energy registers from 14720 count in a unit set by the number of decimal places at register 2393, from 0 (1 kWh) to 4 (0.0001 kWh), default 4. Read 2393 once, divide the counter by 10 to that power and compare the kWh import reading with the display.¹

Why does a 32-bit value read as millions?

The client is taking the high word first. The EM133 sends the low-order word in the first register and the high-order word in the second, for integers and floats alike. Swap the two registers in the Edge point definition.¹

Can Edge read the EM133 over Ethernet?

Yes, when the ETHD Ethernet module, or a 12DIOR module with its Ethernet port, is fitted as COM2. The meter keeps a Modbus TCP server on port 502 permanently and allows two simultaneous Modbus TCP connections. The base meter has only the RS-485 COM1 port and the optical port.^2, 3

Can Modbus writes change the meter's settings?

Yes, but only with the password. The EM133 ships with the password preset to 9 and password protection enabled, and the password applies to the display and the communication ports. Every write must be preceded by the password at register 2575, or the meter answers with exception code 01. A monitoring configuration should read with FC03 only.^1, 2