Why can the correct serial address still fail?

Check the RS-485 operating mode. The manual distinguishes RTU server, RTU master and transparent gateway. A client polling the analyser’s own values needs the server role used here; an existing master or gateway deployment needs its own integration plan.

Does the power value need the CT ratio again?

The selected instantaneous Float entry includes the configured transformer factors. Validate those ratios on the device and do not multiply them a second time in Edge. Other formats and energy tables must be checked independently.

Can polling download the transient records?

An ordinary instantaneous register read does not request the recorded event or transient history. Keep those separate from the read-only telemetry collection described here.

Why can a different format need different scaling?

The map offers several representations. Its general notes distinguish instantaneous Float and short formats, while individual energy tables can add their own ratio and unit rules. Read the definition of the selected entry rather than multiplying every value by the CT ratio.

Janitza UMG 604-PRO: Modbus setup guide

Compatibility

Compatible through Modbus RTU

Janitza documents a local RS-485 measurement interface with the functions, address and data format used in this read-only setup.

UMG 604-PRO with the May 2024 user manual and August 2023 address list for firmware 5.028 and higher. The earlier UMG604 uses a different manual and is outside this guide. Worked commissioning uses the meter’s RS-485 server role, not its master or transparent-gateway role.

Connect it with

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

For the analyser’s own documented server interface

Modbus
Edge
Platforms

Match the installed address, baud rate and framing. Use FC04 for the bounded read below. Record the device identity and configured measurement ratios before collecting totals. The customer-platform output is optional; Edge remains the local system of record.

Models

Download

Models	Interface	Route into Edge
UMG 604-PRO, firmware 5.028+	DIN-rail analyser with RS-485 and Ethernet	This read uses its RS-485 server role.
UMG604 without PRO	Earlier product	Use its own firmware and documentation; no automatic template extension.
UMG604-PRO in master or gateway mode	A different communications role	Do not change the operating role on a working bus merely to run this example.

Specifications

UMG 604-PRO is intended for 35 mm DIN-rail installation and provides four voltage and four current measurement inputs, a temperature input and digital I/O. Its two-button display and integrated Ethernet support a different operating arrangement from a large front-panel analyser. The manual describes local recording of transients longer than 50 microseconds as well as electrical measurements; polling an instantaneous power register does not retrieve those recorded transients.¹

Mounting: 35 mm DIN rail¹
Measurement inputs: Four voltage and four current inputs; one temperature input¹
Interfaces: RS-485, RS-232 and Ethernet; Modbus TCP port 502 is documented¹
RS-485 operating modes: 0: RTU server; 1: RTU master; 2: transparent gateway¹
Digital I/O: Two digital inputs and two digital outputs¹
Recording boundary: Manual describes transients longer than 50 µs; the worked read does not retrieve event records¹
Operating temperature: -10 to +55 °C¹
Selected read: FC04, literal address 19026, two-register Float in W²
Byte-order banks: Printed addresses use big-endian data; add 32768 for the little-endian copy.²

Interface

Documented measurements and integration boundaries for UMG 604-PRO.

Instantaneous phase voltage and current with the configured measurement ratios.
Signed active power and separately identified energy counters.
Model-specific power-quality quantities, distinct from archived event records.
A physical measurement channel and timestamp retained with every collected value.

Assessment

UMG 604-PRO with the May 2024 user manual and August 2023 address list for firmware 5.028 and higher. The earlier UMG604 uses a different manual and is outside this guide. Worked commissioning uses the meter’s RS-485 server role, not its master or transparent-gateway role.

InteroperabilitySupported with conditions: The model-specific manual and map define an open serial measurement path; firmware and interface role must match.^1, 2
AccuracySupported with conditions: The manual defines measurement inputs and capability boundaries. Transformer selection, variant and installation remain part of system accuracy.^1, 2
SecurityNot yet assessed: No authenticated or encrypted telemetry claim is established for this RS-485 path.^1, 2
ReliabilityNot yet assessed: Local recording is described, but continuous end-to-end collection and automatic historical backfill are not established.^1, 2
RuggednessSupported with conditions: The manual states an indoor/cabinet installation and -10 to +55 °C operating range; this is not an outdoor enclosure claim.^1, 2
ScalabilitySupported with conditions: Addressed serial polling and documented register banks permit integration, while actual bus capacity depends on configuration and response timing.^1, 2
LifecycleNot yet assessed: Public documentation is retained, without a stated product support lifetime.^1, 2

Setup

Read total active power

The exact model’s address list places total active power at decimal 19026 as Float in W. The selected instantaneous float includes configured transformer factors.

Read PDU: 04 4A 52 00 02: FC04, address 19026, quantity 2.
Synthetic decoder payload: C4 BB 80 00 decodes as big-endian IEEE754 float32 to -1500.0 W.
Alternate bank: 19026 + 32768 = 51794 (0xCA52) gives the documented little-endian representation.
Scaling: Use the selected Float’s stated engineering unit. Do not apply the configured transformer ratio twice.

Acceptance: These bytes are an independent synthetic decoder example, not a device capture. Verify actual identity, complete response width, selected byte-order bank and agreement with the measurement reference before accepting the reading.

Identify the exact instrument
UMG 604-PRO with the May 2024 user manual and August 2023 address list for firmware 5.028 and higher. The earlier UMG604 uses a different manual and is outside this guide. Worked commissioning uses the meter’s RS-485 server role, not its master or transparent-gateway role.
Verify the measuring configuration
Check the installed voltage and current transformer ratios, wiring system and phase association. The selected instantaneous Float readings include transformer factors; do not transfer that assumption to every integer energy or alternate-format table.
Match the serial role and framing
Read the configured Modbus address, baud rate and serial framing. For UMG604-PRO, use the documented server role only if it matches the intended installation; do not reconfigure an existing master or gateway as a trial.
Read the complete documented quantity
Read FC04 at decimal 19026 (0x4A52), quantity 2, for total active power. Use the printed big-endian bank with a matching Float32 decoder. These are literal map addresses: do not subtract one.
Prove the measurement before expanding
Compare the result with the instrument or a suitable simultaneous reference. Check phase and power direction under a known operating condition, then add documented points with their own widths and units. Keep missing/stale readings separate from zero. Recorded events require a separate retrieval path.

Common questions

Why can the correct serial address still fail?: Check the RS-485 operating mode. The manual distinguishes RTU server, RTU master and transparent gateway. A client polling the analyser’s own values needs the server role used here; an existing master or gateway deployment needs its own integration plan.¹
Does the power value need the CT ratio again?: The selected instantaneous Float entry includes the configured transformer factors. Validate those ratios on the device and do not multiply them a second time in Edge. Other formats and energy tables must be checked independently.¹
Can polling download the transient records?: An ordinary instantaneous register read does not request the recorded event or transient history. Keep those separate from the read-only telemetry collection described here.¹
Why can a different format need different scaling?: The map offers several representations. Its general notes distinguish instantaneous Float and short formats, while individual energy tables can add their own ratio and unit rules. Read the definition of the selected entry rather than multiplying every value by the CT ratio.²

Related devices

Sources

UMG 604-PRO user manual and technical data (opens in a new tab) (PDF) Janitza
UMG 604-PRO Modbus address list and formulary (opens in a new tab) (PDF) Janitza

Cookie	Kept for	What it does
`_ga`	13 months	Tells one browser apart from another across visits
`_ga_<id>`	13 months	Keeps the current visit together
`_clck`	1 year	Tells one browser apart from another across visits
`_clsk`	1 day	Joins the pages of one visit into one recording
`MUID`	1 year	Set by Microsoft on clarity.ms to recognise the browser

Cookie	Kept for	What it does
`li_fat_id`	30 days	Links a visit to the LinkedIn advert click that led to it
`bcookie`	1 year	Set by LinkedIn on linkedin.com to recognise the browser
`lidc`	1 day	Set by LinkedIn on linkedin.com to route requests
`UserMatchHistory`	30 days	Set by LinkedIn on linkedin.com to match visits for advertising
`AnalyticsSyncHistory`	30 days	Set by LinkedIn on linkedin.com to record when it last matched visits