Janitza UMG 96-S2

Compatibility

Compatible with EpiSensor Edge over Modbus RTU

The UMG 96-S2 is compatible with EpiSensor Edge over its RS-485 Modbus RTU port, read through a ZMB-31 Modbus Interface or a Gateway serial port. Janitza publishes the Modbus address list with literal decimal addresses, formats, units and byte order, and the user manual gives its own FC03 request for address 19000.

UMG 96-S2, item 52.34.002, on its own RS-485 port, using the Modbus address list 2.062.026.1.d (06/2025) with user manual 2.062.019.0.l. Site check: read the device address at parameter 0 and compare the first voltage read with the display. Read-only monitoring: no writes to the parameter list, the transformer ratios, the tariff selection or the delete-energy command.

Connect it with

• Modbus Interface ZMB-3X From €399 ex VAT Configure
• Gateway ZGW-20 From €899 ex VAT Configure

Models

Specifications

The UMG 96-S2 is a compact panel analyser for distribution boards: three voltage and three CT current inputs, active, reactive and apparent energy with two tariffs switched over Modbus, harmonics to the 15th for voltage and current, one electrically isolated digital output for S0 pulses and an RS-485 port with Modbus RTU. Operation on the device uses two keys; GridVis software programs and reads it over RS-485.^2, 3

Version

UMG 96-S2, item 52.34.002, supplied with installation instructions, the GridVis quick start, safety instructions and an accessories pack.²

Supply

90 to 265 V AC (50/60 Hz) or 90 to 250 V DC, 300 V CAT III; maximum 1.5 VA / 0.5 W. Internal fuse not exchangeable; 6 to 16 A line protection recommended.^2, 3

Voltage measurement

Three-phase four-wire systems up to 230/400 V in TN and TT networks; 300 V CAT III. Measuring range up to 300 V L-N and 425 V L-L. Values are determined only once V1 exceeds 20 V L-N (four-wire) or 34 V L-L (three-wire).^2, 3

Current measurement

Three inputs for ../1 A or ../5 A current transformers, 0.005 to 6 A, 300 V CAT II; overload 60 A for 1 s.³

Accuracy

Active energy class 0.5S (IEC 62053-22) with ../5 A transformers and class 1 with ../1 A; reactive energy class 1. Voltage and current class 0.2, active power class 0.5 (IEC 61557-12).^2, 3

RS-485

Modbus RTU slave on a three-pole plug: 13 (C, data GND), 14 (A), 15 (B). Device address 1 to 247 (default 1). 9.6, 19.2 or 38.4 kbit/s (default 38.4). 8 data bits; parameter 2 selects 1 stop bit without parity (default), 2 stop bits without parity, even parity or odd parity. No broadcast; telegrams up to 256 bytes.^1, 2

Bus

Up to 32 devices per segment, repeaters beyond that; 1200 m at 38.4 kbit/s. No integrated termination: 120 Ω, 1/4 W at both ends. Janitza recommends Unitronic Li2YCY(TP) 2 × 2 × 0.22 cable and says CAT cables are not suitable.²

Digital output

One semiconductor relay output on terminals 16 and 17 for active, reactive or apparent energy pulses; up to 60 V DC and 50 mA, pulses up to 12.5 Hz.^2, 3

Mounting and environment

96 × 96 mm front-panel device for a 92 × 92 mm cut-out, about 250 g. -10 to +55 °C in operation, 0 to 75% RH. IP40 front, IP54 front with seal, IP20 rear; IK07; weather-protected stationary use.^2, 3

Interface

Documented measurements and integration boundaries for UMG 96-S2.

• Addresses are literal decimal PDU addresses: 19000 is sent as 4A 38. Read with FC03, two registers per Float, IEEE-754 single precision, high byte first. Registers update every 200 ms.
• L1-N, L2-N and L3-N voltage at 19000, 19002 and 19004; L1-L2, L2-L3 and L3-L1 voltage at 19006, 19008 and 19010: V.
• L1, L2 and L3 current at 19012, 19014 and 19016; current sum (the calculated neutral current) at 19018: A.
• L1 to L3 active power at 19020, 19022 and 19024, total active power at 19026: W. Apparent power at 19028 to 19034 (VA) and reactive power at 19036 to 19042 (var), each with the total last.
• Power factor L1, L2 and L3 at 19044, 19046 and 19048 (the manual calls these the fundamental power factor, cos φ); frequency at 19050 (Hz). The 1000 block carries power factor at 1012 to 1018 and cos φ at 1032 to 1038 separately.
• Active energy L1, L2, L3 and sum at 19054 to 19060; consumed at 19062 to 19068; delivered at 19070 to 19076: Wh.
• Apparent energy at 19078 to 19084 (VAh), reactive energy at 19086 to 19092, inductive at 19094 to 19100 and capacitive at 19102 to 19108 (varh), each with the sum last.
• Voltage THD L1-N to L3-N at 19110 to 19114 and current THD L1 to L3 at 19116 to 19120: %.
• The same energies as 64-bit doubles start at 3000, four registers each: active energy sum at 3012, consumed sum at 3028 and delivered sum at 3044. Tariff 1 and tariff 2 counters follow, from 3112 and 3224.
• Rotation field at 19052 (1 right, 0 none, -1 left): the address list gives it as int and the manual's table as float, so decode it only after comparing with the display.
• Float values already include the configured CT and VT ratios; values in short format do not. Add 32768 to an address only to read the same value little-endian.
• Parameters 0 to 624 (device address, baud rate, framing, transformer ratios, password, tariff selection, delete min/max and delete energy) are read/write. Keep FC06, FC16 and FC23 out of a monitoring poll.

Setup

1. Identify the analyser

   Read UMG 96-S2 on the front and the item number on the rating plate, and note whether another master, such as a Janitza UMG 512-PRO, already polls its RS-485 port.

2. Read the communication settings

   In programming mode, open the parameter list and read address 000 (device address), 001 (baud rate) and 002 (framing). The defaults are address 1, 38.4 kbit/s, 8 data bits, no parity and 1 stop bit. Enter the same values in the Edge serial client; if a user password is set, the analyser asks for it first.

3. Wire the RS-485 pair

   Connect A to terminal 14, B to 15 and data GND to C on 13 with twisted, shielded cable, and give each device on the segment its own address. Fit a 120 Ω, 1/4 W resistor at both ends of the segment, earth the shield at the cabinet entry and never on terminal C. The manual also recommends connecting terminal C to PE as functional earth.

4. Make two reads

   Read parameter 0 with FC03, one register, and expect the device address. Then send FC03 to decimal address 19000 (0x4A38) for two registers and decode the Float32 high byte first, as in the worked read below. Compare the result with L1-N voltage on the display.

5. Add the points you need

   Add current at 19012, total active power at 19026 and frequency at 19050, then the energy counters consumed at 19068 and delivered at 19076. Keep FC06, FC16 and FC23 writes out of the polling configuration.

Common questions

Is 19000 the register number or the address on the wire?

It is the address on the wire. The manual's request example sends 19000 as start address 4A 38, so enter 19000 in a client that takes zero-based PDU addresses and 19001 in one that numbers registers from one.²

Which serial settings does the UMG 96-S2 use?

8 data bits at 9.6, 19.2 or 38.4 kbit/s, with 38.4 kbit/s as the default. Parameter 2 sets the framing: 0 is 1 stop bit without parity (the default), 1 is 2 stop bits without parity, 2 is even parity and 3 is odd parity, each with 1 stop bit. The address list's transfer-parameter page names only odd and even parity, so read parameters 1 and 2 on the analyser rather than assuming.^1, 2

Do I need to multiply by the CT ratio?

Not for the Float values. The address list states that values in float or integer format include the configured transformer factors, while values in short format do not. Compare current and power with the display under load before trusting the energy counters.¹

Which energy register is total consumption?

Active energy consumed, sum of L1 to L3, at 19068 in Wh, with delivered energy at 19076 and the active energy sum at 19060. The manual's table labels 19068 as rate 1; when tariffs are switched over Modbus, the tariff 1 and tariff 2 counters are at 4070 and 4126 as floats, or 3140 and 3252 as doubles. Compare the chosen register with the display before using it.^1, 2

Can Edge read a UMG 96-S2 that a Janitza master already polls?

Not on the same RS-485 segment. The manual shows a UMG 512-PRO as the master of a UMG 96-S2 bus, and a Modbus RTU bus has one master. Agree with the site whether Edge takes over that bus before connecting it. The UMG 96-S2 itself has no Ethernet port.²

Can I reuse a point list from another Janitza UMG?

Check every address against the UMG 96-S2 list first. Its 19000 table has active energy L1 to sum at 19054 to 19060, consumed at 19062 to 19068, delivered at 19070 to 19076 and reactive energy at 19086 to 19092, and other UMG models do not all use the same assignments in that block.¹