SITRANS LR460 HART DTM: Configuration via Siemens PDM

Overview

The SITRANS LR460 is a 4-wire 24 GHz FMCW radar level transmitter from Siemens designed for continuous, non-contact level measurement of bulk solids in silos, stockpiles, crushers, and transfer points. Although the device is fully HART-compliant on its 4–20 mA loop, Siemens does not publish a device-specific HART DTM (Device Type Manager) for generic FDT-frameworks such as PACTware. The vendor-issued LR460 HART DTM exists only inside SIMATIC PDM; a separate PROFIBUS PA DTM and an EDD for the legacy Rosemount 375/475 handhelds round out the available configuration ecosystem.

Field engineers routinely hit the dead-end described here: they download SITRANS_DTM_V4.1.0.2049 from Siemens entry 109484287, install it into PACTware 5.x, and discover that no device DTM appears for the LR460. That file is the framework DTM, not the device DTM. The LR460 device HART DTM is shipped in the SIMATIC PDM device library, not in the SITRANS DTM V4.1 package.

SITRANS LR460 Communication Interfaces

The two-wire variant (LR460 with HART output) and the four-wire variant share the same firmware; the difference is in the terminal block and the output board. Either variant is configured with the same HART DTM in PDM.

DTM Architecture: Framework vs. Device DTMs

FDT/DTM (Field Device Tool / Device Type Manager) is a two-layer model. The frame application (PACTware, FieldCare, PDM) provides the project, communication channel, and topology editor. The DTM is a DLL or ActiveX/COM component supplied by the device vendor that exposes the device's parameter tree, methods, and diagnostics. PACTware cannot talk to a SITRANS device with a framework DTM alone — it also needs the matching device DTM.

HART DTM Availability Matrix

Path 1 — SIMATIC PDM + USB/HART Modem (Recommended)

This is the only path that exposes every LR460 parameter, including Siemens-specific echo processing, auto-false-echo suppression, and the diagnostic counters that are not part of the public HART DD.

Prerequisites

• Windows 10 / 11 (x64) with SIMATIC PDM V8.2 SP3 or V9.2.x installed.
• SITRANS LR460 HART device DTM is bundled with PDM; ensure the device catalog is up to date (Device Catalog > Update).
• USB/HART modem: Mactek Viator USB HART (0102-XXXX), ifm USB-2-HART, or Pepperl+Fuchs FDT-USBMOD. The modem must be a HART master (primary or secondary); slave-only modems will not enumerate the LR460.
• 250 Ω loop resistor if the LR460 loop is powered from a non-HART-compatible source (most modern DCS cards supply this internally; check the AI card spec — at least 250 Ω must remain in the loop at 4 mA).
• HART short address = 0 (factory default) or a polled address if multidrop.

Commissioning Workflow

1. Connect the USB/HART modem in parallel with the loop. Polarity is not critical on the modem; observe + / - on the LR460 terminal block.
2. Power the loop (24 VDC typical, 14 mA quiescent). The LR460 will perform a self-test (~30 s) and begin searching for a valid echo.
3. Launch SIMATIC PDM, create a new project, then Plant View > Add Device > SITRANS LR460. PDM will insert the device DTM automatically.
4. Right-click the device, choose Connect. The first poll will read the unique HART long tag, descriptor, message, and final assembly numbers (typically 0x0001 / 0x0002 for HART 6, 0x0101/0x0102 for HART 7 burst-mode devices).
5. Open Parameter > Quick Start Wizard. Set the application type (silo, stockpile, crusher, transfer point), vessel empty distance E, and full distance F. The LR460 computes span = F − E and writes the upper range value to the AO transducer block.
6. Run Auto False Echo Suppression from the echo menu. This writes the learned echoes to a non-volatile curve. Repeat any time the internal obstructions change (e.g., new ladder, new agitator).
7. Configure damping (default 10 s; range 0–600 s in 0.1 s steps), failure mode (hold last value / 22.0 mA / 3.6 mA per NAMUR NE43), and HART burst mode if needed.
8. Download to device. PDM will display a comparison screen showing differences between offline and online values; tick Only modified for the minimum write set.

Verification

• Read the primary variable (PV) and verify it tracks the actual level. Drive a step change with a 4–20 mA calibrator and confirm PV tracks within the configured damping.
• Read the loop current (Diagnostics > Loop Current). It should equal the PV-mapped current to within ±0.01 mA.
• Read HART universal command 48 (additional device status). Bytes 0–5 should be 0x00; any non-zero value points to a diagnostic condition listed in Diagnostics > Status.
• Write HART command 33 to read the PV damping value and compare with the configured damping.

Path 2 — PACTware + Generic HART DTM

This path is the fallback when SIMATIC PDM is unavailable. Functionality is limited to HART universal and common-practice commands; Siemens-specific features (false-echo suppression curve, echo confidence, false-echo histogram) are not exposed.

Install Order

1. Install PACTware 5.0.x (CodeWrights GmbH — download from pactware.com).
2. Install the SITRANS DTM V4.1 framework: 20161215_Siemens_SITRANS_DTM_v4.1.0.2049.zip from Siemens entry 109484287.
3. Install a generic HART communication DTM (CodeWrights HART Communication DTM, FDT 1.2 / FDT 2.0 compatible). This DTM provides the modem channel and a generic menu driven by the device EDD.
4. Connect the LR460 EDD into PACTware's device catalog. PACTware's generic HART DTM can read an EDD; Siemens publishes the LR460 EDD as part of the PACTware device library bundle or as a separate HCF registration.

Accessible Parameters (via Generic HART DTM)

• Tag (8-byte), Long Tag (32-byte HART 7), Descriptor, Message, Date.
• PV range units (m, ft, in, %, cm) and PV damping time.
• Transfer function: linear, square root, square root of 3rd power (for volume vessels), or custom 32-point table.
• Loop current trim (4 mA and 20 mA DAC trim, D/A trim commands 45/46).
• Sensor trim (HART command 49: sensor high/low trim) — usable on the LR460 echo curve only with limitations.
• Polling address (0–15) for multidrop.

Items Not Exposed in Generic DTM

• Auto false-echo suppression and the learned false-echo table.
• Empty distance E and full distance F (writes require device-specific DTM; PDM only).
• Echo curve view and snapshot export.
• Siemens-specific diagnostic counters (lost-echo, peak-hold, tank-bottom-tracking status).

Path 3 — Rosemount 375/475 Handheld Communicator

The 375 and 475 HART communicators (originally Rosemount, now Emerson) load the LR460 EDD as a device driver. The communicator is treated as a HART master, so it can fully configure the LR460 without a PC, but Siemens stopped actively shipping updated EDDs to the Emerson 375/475 library. 375/475 hardware is no longer supported by Emerson as of January 2020; AMS Trex is the current Emerson platform.

Menu Path on the 375/475

1. From the home screen, choose Device Setup > Connected > LR460 (the EDD will display Siemens Milltronics SITRANS LR460).
2. Open Configure > Setup > Basic Setup. Set the device tag, PV unit, and range values (LRV/URV).
3. Open Configure > Setup > Empty/Full. Enter the empty distance E (process connection face to the empty level point) and the full distance F (typically the silo height minus a safety margin of 0.5 m).
4. Open Configure > Diagnostics > Echo Profile to view the live echo curve; use Service Tools > Auto False Echo Suppression to start the learn cycle.
5. Open Configure > HART > Output > Burst Mode. Configure burst message 1 (PV) and message 2 (PV + current + %range) if the host DCS supports HART burst.

Limitations

• 275 Ω loop resistor required if the 375/475 is in series with the loop.
• Battery-powered communicator draws < 20 mA from the loop only when in online mode; otherwise it is line-powered.
• No bulk export of configuration; each parameter must be entered manually. Use the Save Config to File option (475 only) to back up the offline configuration.

Installing the SITRANS DTM V4.1 Framework

The framework DTM SITRANS_DTM_V4.1.0.2049 (build date 2016-12-15) is the canonical Siemens HART framework DTM. It registers as a PACTware communication DTM and as a device-catalog host. The build is compatible with PACTware 5.0.x; it will also load into newer PACTware 5.x builds but is not FDT 2.0 native.

Installation Steps

1. Unzip 20161215_Siemens_SITRANS_DTM_v4.1.0.2049.zip to a local folder.
2. Right-click setup.exe and run as administrator. The installer registers SiemensHARTComm.dll in the Windows registry under HKLM\SOFTWARE\Wow6432Node\PACTware\DTMs (32-bit view) on a 64-bit OS.
3. Launch PACTware. Open Device Catalog > Update. The catalog will enumerate SITRANS DTM V4.1 under Siemens AG. Click Add to project to instantiate it as a host DTM.
4. Right-click the framework DTM and select Connect. The DTM will fail to open a channel against an LR460 with the message "No device-specific DTM found for tag" — this is expected behaviour. The framework cannot be used as a substitute for a device DTM.

Obtaining Export-Restricted Software

Siemens Industry Online Support classifies SITRANS_DTM_V4.1.0.2049 as export-restricted software. Public download links return a login wall until the requesting account passes the export-control check. The check verifies nationality and the country of business, then issues a per-account entitlement that is re-validated every 24 months.

Registration Workflow

1. Create a Siemens Industry Online Support account at support.industry.siemens.com.
2. From the user profile, request Export-Restricted Authorization. Upload the requested identity documents (passport or national ID for individuals; trade-register extract for companies). Typical processing time: 2–5 business days.
3. Once approved, the download at entry 109484287 becomes available without the login redirect.
4. The entitlement is valid for 24 months. Siemens will send an email reminder; failure to reconfirm triggers a new document re-check.

Device Parameters and Configuration Items

The following parameters are accessible in SIMATIC PDM with the LR460 HART DTM. Items marked device-specific are not exposed by the generic HART DTM in PACTware or by the public EDD.

Troubleshooting Matrix

Frequently Asked Questions