Configuring 4-Value Display on Siemens IOP for SINAMICS G120

1. Problem Overview

The Intelligent Operator Panel (IOP) for the SINAMICS G120 drive family is designed to surface a multi-parameter status screen directly on the device. On a CU 240E-2 Control Unit coupled with a PM 240 Power Module, however, an operator or commissioning engineer can find that the status display only accepts two process quantities — typically a primary value (e.g., output frequency or speed) and a secondary value (e.g., motor current). When an application requires four quantities such as output voltage, motor current, active power (kW), and motor speed (RPM) to be monitored simultaneously on the IOP main screen, the firmware-imposed limit becomes the visible constraint.

This limitation is not a defect of the hardware, the CU, or the PM 240. The IOP's own firmware controls how many scalar values can be placed on the status screen. Firmware version 1.4 only supports two scalar values. Firmware version 1.5 and later expands the status display to four scalar values, which is the documented limit for the IOP-1 (first-generation IOP). The IOP-2 has separate firmware and is not subject to this 1.4/1.5 distinction.

This article documents the identification, root cause, firmware upgrade procedure, parameter configuration, and verification steps required to recover the full four-value status display on an IOP connected to a CU 240E-2 / PM 240 combination.

2. Affected Hardware and Firmware

3. Root Cause Analysis

The IOP status display is implemented as a configurable multi-value dashboard. The firmware release history documents the following change:

When a CU 240E-2 is shipped with an IOP shipped from inventory in 2014–2016, the IOP frequently carries V1.4. The control unit firmware (V4.5 or V4.6 in the field example) is unrelated to the IOP's display capacity. A commissioning engineer therefore sees a working drive, a fully functional IOP menu tree, and a two-value limit on the main screen that cannot be cleared through parameter changes inside the inverter firmware. The only corrective path is a firmware upgrade of the IOP itself.

4. Prerequisites

Before upgrading the IOP firmware or configuring the four-value status display, confirm the following:

1. IOP-1 identification. Check the label on the rear of the IOP or the menu path Menu → Diagnostics → IOP Info to confirm the panel model and current firmware version.
2. Compatible Control Unit firmware. IOP-1 firmware V1.5/V1.6/V1.7 is compatible with CU firmware V4.4 and later. For CU 240E-2 with firmware V4.6, IOP firmware V1.5 or higher is required.
3. Latest IOP-1 firmware package. Download the firmware ZIP from the Siemens Industry Online Support entry ID 109476464. The ZIP contains the IOP-1 firmware binary (typically IOP1_Vxx_xx.zip) and release notes. Reference: Siemens Support Entry 109476464 — IOP Intelligent Operator Panel Firmware Download.
4. Empty microSD or USB stick. The IOP-1 accepts a firmware image loaded on a microSD card (FAT32 formatted) inserted into the IOP microSD slot. Some IOP-1 hardware revisions also accept an MMC card; check the slot on the rear of the panel.
5. Drive in a safe state. Although the IOP can be upgraded with the drive powered, the inverter should be in STOP state with the enable signals removed (OFF1/OFF2/OFF3 inactive, pulse inhibit active).
6. Access to drive parameters. Have the parameter list for r0021, r0025, r0027, r0032 (or equivalents) available. These are read-only "actual value" parameters (r-parameters) and do not require a parameter set password.

5. IOP Firmware Upgrade Procedure (IOP-1, V1.4 → V1.5 or later)

1. Power down the drive. Remove the 24 V control voltage and the line voltage. Wait for the DC link discharge LEDs on the PM 240 to extinguish completely (typically 5 minutes for FSA–FSC; up to 15 minutes for FSD–FSF).
2. Prepare the memory card. Format a microSD card as FAT32 (32 GB maximum supported). Extract the firmware file from the downloaded ZIP and copy the binary to the root of the card. The card should contain only the firmware update file; do not place any other files on the card during the upgrade.
3. Insert the memory card. With the drive still de-energized, remove the IOP from the CU 240E-2 by tilting the panel forward and lifting. On the rear of the IOP, locate the microSD slot. Insert the prepared card with the contacts facing the slot as labeled on the panel housing.
4. Power up the drive. Reapply control voltage (and line voltage if required for the upgrade). The IOP will boot and detect the firmware update file on the card.
5. Confirm the upgrade prompt. The IOP displays a message such as "Firmware update found on memory card. Update?" Navigate to Yes and press OK. The upgrade takes approximately 2–4 minutes; do not interrupt power during this window.
6. Wait for completion. The IOP will reboot automatically when the update completes. Verify the new firmware version under Menu → Diagnostics → IOP Info → Firmware version. The reported version should be V1.5, V1.6, or V1.7 depending on the file applied.
7. Remove the memory card. Once the new version is confirmed, power down the drive again, remove the microSD card, reattach the IOP to the CU, and power up.
8. Verify the four-value option is now available. Navigate to Menu → Setup → Status Display or Menu → Parameters → Display Settings. The IOP should now offer four scalar value slots instead of two.

6. Configuring the Four-Value Status Display

After upgrading the IOP to V1.5 or later, the operator panel exposes the Scalar Value Display Mode, which can show up to four parameter values simultaneously. The configuration is performed entirely from the IOP keypad.

1. From the main menu, navigate to Setup → Status Display.
2. Select Scalar Value Display Mode. The IOP presents four selection slots (Slot 1 through Slot 4).
3. For each slot, browse to the desired r-parameter. Use the up/down navigation to scroll the parameter list; the IOP groups r-parameters into intuitive categories (Speed, Voltage, Current, Power, Temperature, I/O, etc.).
4. Assign the four parameters per the application requirement. For monitoring output voltage, current, kW, and RPM, use the parameter assignments shown in the table below.
5. Press OK to save the configuration back to the IOP. The main screen now displays the four values in a 2×2 grid with units.

7. Recommended Parameter Mapping for Voltage / Current / kW / RPM

The SINAMICS G120 parameter list provides smoothed actual-value parameters suitable for status display. The following assignment delivers a typical engineer-friendly dashboard:

Alternate parameters that may be substituted depending on the application:

8. Alternative Configuration via STARTER / TIA Portal

While the IOP scalar display is configured locally on the panel, the underlying drive parameters can also be parameterized from STARTER (classic) or TIA Portal (V15 and later, with SINAMICS Startdrive). Both tools allow the same read-only r-parameters to be monitored and trended.

1. Open the project in TIA Portal with the SINAMICS Startdrive option installed.
2. Online-connect to the CU 240E-2 over PROFINET or PROFIBUS (PN or DP variant).
3. Navigate to Parameters → r0021 / r0025 / r0027 / r0032 in the parameter list and add each to a watch table or a custom HMI tag set.
4. Confirm the values displayed on the IOP match the values read back by the commissioning tool. Any discrepancy indicates the smoothing time p0045 or scaling p0008 is misaligned.

Reference for parameter list: SINAMICS G120 CU240E-2 List Manual — Parameter List.

9. Verification Steps

After the firmware upgrade and parameter assignment, perform the following verification:

1. Firmware version check. Confirm IOP firmware is now V1.5 or later via Menu → Diagnostics → IOP Info.
2. Status display check. From the main screen, navigate through Menu → Setup → Status Display and confirm four slots are available.
3. Visual readout. Return to the main screen and verify four values are displayed in the 2×2 grid with correct units (V, A, kW, RPM).
4. Setpoint response. Issue a run command with a moderate speed setpoint. Observe that all four values update in real time and remain stable.
5. Cross-tool check. Using STARTER or TIA Portal, read back the same r-parameters via PROFIBUS/PROFINET and confirm they match the IOP display within the smoothing tolerance.
6. Power cycle. Remove and reapply 24 V control voltage. Verify the IOP retains the four-value configuration. (Scalar display mode configuration is stored in the IOP's non-volatile memory; the assignment persists across reboots.)

10. Troubleshooting Matrix

11. Safety and Commissioning Notes

• Insulation and ESD. Observe ESD precautions when handling the IOP and the microSD card. The IOP contains ESD-sensitive components; use a grounded wrist strap when removing the panel from the CU.
• Live work prohibition. Never insert or remove the microSD card with the IOP powered. The IOP slot does not support hot-swap of the memory card.
• Drive state during upgrade. Although the upgrade can be performed with the drive powered, the drive must be in STOP state with all enable signals (OFF1, OFF2, OFF3) removed. The control word from a higher-level PLC (e.g., SIMATIC S7-1500 via PROFINET) must not be enabling the drive during the upgrade window.
• Firmware compatibility matrix. Always consult the release notes for the IOP firmware before applying. Siemens publishes a release note PDF inside the firmware ZIP that lists compatible CU firmware versions. Reference: Siemens Support Entry 109476464.
• Parameter set password. The four-value status display configuration is stored on the IOP, not in the drive parameter set. It is not affected by p0011 (commissioning lock) or p0012 (parameter key lock) on the CU.
• BOP-2 alternative. If the four-value display is not critical, the BOP-2 (Basic Operator Panel) is a low-cost alternative that displays a single value via 7-segment readout. The BOP-2 does not support scalar value display mode at all.

12. Reference: IOP-1 Firmware Version Compatibility

For the official IOP-1 firmware download and release history, refer to Siemens Support Entry 109476464 — IOP / IOP-2 Firmware. For SINAMICS G120 CU240E-2 documentation including the parameter list and operating instructions, refer to the SINAMICS G120 CU240E-2 List Manual and the SINAMICS G120 Operating Instructions.