Configuring SIMOCODE Pro C Standalone: Direct Starter Without PLC

Overview

The Siemens SIMOCODE Pro C is a modular motor management and protection device that ordinarily sits on a Profibus DP or Profinet segment behind a SIMATIC controller. In retrofit or brownfield MCC applications, however, the same unit must sometimes operate in true standalone mode: no Profibus/PROFINET master, no operator panel, no PC connection, only a hard-wired start/stop pushbutton station, a reset pushbutton, and a fault indicator lamp. This configuration is sometimes called a "direct-on-line starter in a box" and it is the cleanest way to reuse an existing SIMOCODE Pro C as a spare unit in a withdrawable MCC bucket.

This reference walks through the exact parameter changes in SIMOCODE ES V20 (TIA Portal) required to make a SIMOCODE Pro C act as an autonomous motor starter, while keeping every standard SIMOCODE protection function active. The procedure assumes a SIMOCODE Pro C base unit (3UF7000-1A.0-0 or -1A.0-1, depending on Profibus/Profinet variant) paired with a 3UF7100-1AA00-0 current measuring module sized to the motor.

Prerequisites

• SIMOCODE Pro C base unit, 3UF7000 series, with current measuring module (3UF7100) matched to motor FLA.
• SIMOCODE ES V20 or later, installed and licensed. The TIA Portal variant is preferred for projects that also contain SIMATIC controllers; the classic SIMOCODE ES 2007 SP4 (PCS 7) variant is acceptable for standalone use.
• USB PC cable (3UF7940-0AA00-0) or Ethernet/Profinet for Pro V/PROFINET variants, to download the project to the device.
• 24 V DC control supply for the base unit and for the digital inputs.
• Hard-wired control station: Start (NO), Stop (NC), Reset (NO) pushbuttons, and a fault indicator lamp or stack-light.
• Motor nameplate data: rated current (Is1), service factor, trip class, and rated voltage.

SIMOCODE Pro C Hardware Architecture

The base unit is the only component that matters for standalone wiring. The relevant on-board I/O of a 3UF7000-1A base unit is summarized below.

The base unit also carries two 4-position rotary address switches S1 and S2 on the front. In bus mode these select the Profibus DP slave address (1–125). In standalone mode, S1 and S2 are repurposed by the SIMOCODE ES configuration to select the active control station, or they can be set to "fixed level" so the software override is in effect regardless of switch position.

Control Station Selection for Standalone Operation

SIMOCODE Pro offers four control stations. They determine which source is allowed to issue commands (ON, OFF, Reset) and to read status.

For a fully autonomous starter, set the selector for S7/DP control station to PLC = inactive and select Local2 as the only issuing control station. In SIMOCODE ES this is done by opening the project, navigating to Control stations → Control function → Sources for commands, and checking the box for Local 2 while clearing the boxes for PLC/PROFIBUS and Local 3.

Two implementation choices exist for the S1/S2 selector on the base unit:

1. Fixed level in software — Open the device properties, expand Control station selector, and set S1 = fixed level 0 and S2 = fixed level 1. The hardware switches are then ignored. This is the preferred approach for a stand-alone spare unit that may be inserted into any bucket.
2. Hardware selector — Leave S1 and S2 at "not fixed" and document the required switch position on the bucket door. Acceptable when the SIMOCODE will never be moved.

Reset Input Configuration

By default the SIMOCODE ES V20 direct-starter template wires the Reset command to the Cyclic Receive, bit 0.7 from the Profibus master. In standalone mode that bit never toggles, so a latched fault can never be cleared. The Reset source must be re-pointed to a hard-wired input.

In the graphic editor, perform the following edits in this order:

1. Delete the Cyclic Receive 0 function block from the program (right-click → Remove). This removes the wired Reset-from-PLC link.
2. Insert a new Reset function block and connect its output to the SIMOCODE internal Reset signal.
3. Source the Reset block from Input 3 (Base Unit). To do this, open the Reset block's properties and set the Signal source parameter to DI Base Unit → Input 3.
4. Configure the input as normally open, 24 V DC, debounce time 20 ms (default).

When the operator presses the Reset pushbutton, Input 3 closes to 24 V, the SIMOCODE internal Reset bit sets for the duration of the press plus one scan, and any latched fault is cleared after the configured cooling time has elapsed.

Fault Output Configuration

By default, Cyclic Send 0 is wired to the QLS (Fault) flag so the PLC can display the fault. In standalone mode that bus is gone. Re-wire QLS to a base-unit output so a stack-light can indicate the fault.

1. Delete the Cyclic Send 0 and any Cyclic Send 1 function blocks.
2. Open the QLS ‒ Fault block and set Output target to DO Base Unit → Output 2.
3. Output 2 is a changeover relay. Wire the normally-open contact of Output 2 to the fault lamp; the normally-closed contact can drive a healthy-run lamp or be left unused.

Optional: route the QAS (Operating state → ON) flag to Output 3 to indicate "motor running". This gives the operator both a green run light and a red fault light without any panel.

Motor Overload Protection Setup

The overload function is the reason SIMOCODE Pro is used in the first place. Three parameters are critical:

For a 400 V, 50 Hz, 11 kW motor with FLA 21 A the entries would be:

Set current Is1      = 21.0 A
Trip class           = CLASS 10
Cooling time         = 300 s
Phase failure prot.  = ON (recommended for all three-phase motors)
Phase rotation       = Indifferent (unless the application is unidirectional)
Unbalance detection  = 30 % (default)

SIMOCODE Pro uses a thermal model: I²t is integrated continuously. After a trip the device blocks restart until the calculated thermal image has decayed below 75 % (or whatever the recovery threshold is set to). The Reset pushbutton is only effective after this cooling period has expired, which prevents an immediate re-trip from a hot motor.

Cyclic Data Block Handling

Once the Reset and QLS blocks have been redirected to base-unit I/O, all cyclic send and receive blocks should be removed. The TIA Portal will display warnings if you attempt to download a project that still references a Profibus slave that does not exist. The clean-up sequence is:

1. Right-click each Cyclic Receive block and select Remove.
2. Right-click each Cyclic Send block and select Remove.
3. Open Device properties → Communication → PROFIBUS DP and uncheck Activate PROFIBUS DP. This removes the slave from the project entirely.
4. Compile and download. SIMOCODE ES will report "Project does not contain a DP slave" — this is the expected result.

Fault Reset Behavior and Cooling Time

There are four reset modes in SIMOCODE Pro:

Set the reset mode in Protection functions → Overload → Reset to Manual, edge-triggered. Verify that the cooling time is long enough to let the motor cool — a typical 4-pole 11 kW TEFC motor needs about 5 minutes. If the operator can re-trip the motor within 10 seconds of a Reset, the cooling time is set too short.

Step-by-Step Configuration Procedure

1. Open SIMOCODE ES V20 and create a new project for the device order number 3UF7000-1A.0-0 (or -1A.0-1 for PROFINET variant).
2. Select the Direct starter (reversing starter disabled) function template.
3. Open Control stations and set PLC/DP control station to Inactive. Enable Local 1 (PC) for diagnostics, Local 2 (DI on device) for commands, and Local 3 (operator panel) to Inactive.
4. Open Control function → Sources for commands and confirm the ON/OFF source is the hard-wired inputs (Input 1 for Stop, Input 2 for Start).
5. Open the graphic editor. Delete the Cyclic Receive 0 block. Re-wire Reset to Input 3 of the base unit.
6. Delete the Cyclic Send 0 block. Re-wire QLS (Fault) to Output 2 of the base unit. Optionally re-wire QAS to Output 3.
7. Open Protection functions → Overload. Enter Is1 from the motor nameplate, set trip class 10, cooling time 300 s, and select manual edge-triggered reset.
8. Open Device properties → Communication → PROFIBUS DP and deactivate the slave. Compile the project.
9. Connect the PC to the base unit with the USB cable (3UF7940-0AA00-0). In SIMOCODE ES, click Load to device and accept the default node address 0.
10. Power-cycle the base unit to activate the new configuration.

Verification and Commissioning

After download, run a structured functional test before the unit is inserted into the live MCC.

1. Power-on test: Apply 24 V DC control power. The green "Ready/On" LED on the base unit should illuminate within 1 second. The red fault LED should be OFF.
2. No-load start: Briefly press the Stop pushbutton (verify it is wired NC, not NO). Press Start. The contactor should pull in. Output 3 (run light) should energize.
3. Stop test: Release Start, then press Stop. The contactor should drop out immediately.
4. Fault simulation — overload: With the motor stopped, open SIMOCODE ES → Test → Force fault → Overload. The fault LED should latch ON, Output 2 should energize, and the contactor should be blocked from re-starting.
5. Reset during cooling: Press Reset immediately after the fault. The fault should remain latched (cooling time not yet elapsed).
6. Reset after cooling: Wait 5 minutes (or the configured cooling time). Press Reset. The fault should clear. The fault LED should go OFF, Output 2 should de-energize, and a new Start command should be accepted.
7. Power-loss test: Remove 24 V control power with the contactor pulled in. Restore power. The contactor must NOT restart automatically — SIMOCODE Pro C will be in the stopped state, requiring a fresh Start command. This is the correct fail-safe behavior.

Troubleshooting Matrix

Spare-Unit Best Practices

When the SIMOCODE Pro C is held as a hot spare, observe the following field-proven rules:

• Store the unit with the 3UF7100 current measuring module already bolted to it, wired with short pigtails. The module range must match the bucket it is intended for.
• Keep the latest project file (the .zap17 or .zap20 export) in a labeled envelope on the spare. The same file is also stored in the project archive.
• Pre-set S1 and S2 to fixed levels in software so the spare can be installed without switch adjustment.
• Mark the bucket door with the required motor nameplate data. The maintenance crew must update Is1 in the project if the new motor has a different FLA.
• After every swap, repeat the full verification procedure from this article before re-energizing the feeder.

Field Commissioning Checklist

[ ] Motor nameplate data recorded: kW, V, A, rpm, cos phi, service factor
[ ] Current measuring module range matches motor FLA
[ ] SIMOCODE ES V20 project created, direct starter template
[ ] Control station S7/DP disabled, Local 2 enabled
[ ] Reset block wired to Input 3
[ ] QLS block wired to Output 2
[ ] Is1 entered, trip class selected, cooling time set
[ ] PROFIBUS slave deactivated in project
[ ] Project compiled and downloaded to device
[ ] Power-on LED check passed
[ ] No-load start/stop test passed
[ ] Forced overload fault latches
[ ] Reset after cooling time clears fault
[ ] Power-loss test confirms no auto-restart
[ ] Fault indicator lamp and run lamp wired and tested
[ ] Spare unit labeled with project filename and revision date