Configuring Siemens MM440 for Local/Remote Operation Using CDS

Overview

The Siemens MICROMASTER 440 (MM440) supports two independent Command Data Sets (CDS0 and CDS1) and three independent Drive Data Sets (DDS0–DDS2). A Command Data Set groups the parameters that define where the drive receives its run command and where it receives its speed setpoint. By writing one set of parameters for index [0] and another set for index [1], a single MM440 can be switched between two completely different control schemes using a single hardware selector input.

This reference covers the canonical industrial case:

• Remote mode (CDS0) – run command from a terminal push button, speed setpoint from a 0–10 V or 4–20 mA analog signal sourced by a PLC.
• Local mode (CDS1) – run command from the same terminal push button, speed setpoint generated internally by the Motor Potentiometer (MOP) function, ramping up/down from a configurable fixed starting frequency.

The Local/Remote hand-off is performed by a single selector switch wired to DIN4, which is internally routed via P0810 to the active-CDS bit. No PLC re-programming, no fieldbus toggle, and no BOP key sequence is required at the panel.

Prerequisites

1. MM440 inverter, any frame size (A through F) with firmware ≥ 1.0. The CDS feature is available on all production MM440 units; the procedure here is valid for firmware versions 1.x, 2.x, and 3.x.
2. Basic Operator Panel (BOP) or Advanced Operator Panel (AOP) connected to the front RS-232 port for parameter entry.
3. Three-wire start/stop push-button station (Start – N.O., Stop – N.C.) wired to DIN1 and +24 V.
4. Local/Remote selector switch (1-pole 2-position maintained) wired to DIN4 and +24 V.
5. For local mode MOP raise/lower: two momentary N.O. push buttons wired to DIN2 and DIN3.
6. For remote mode: PLC analog output module (0–10 V on terminals 3/4 or 4–20 mA on terminals 10/11).
7. Motor nameplate data available for P0304–P0311 (rated voltage, current, power, cos φ, frequency, RPM).

System Architecture and Operating Modes

The MM440 evaluates the active CDS at every control cycle (1 ms). When P0810 is configured to a digital input, the logical state of that input becomes the active-CDS selector:

The selector bit does not need to be re-latched, debounced in software, or confirmed to the PLC – the MM440 performs the switch atomically on the next scan. The active CDS is reported in parameter r0050 (bit 0 of the active command word) for diagnostic read-back via USS/PROFIBUS or via the BOP.

Command Data Set (CDS) Parameter Strategy

The two parameters that drive 90 % of a CDS implementation are P0700 (command source) and P1000 (setpoint source). Both are indexed:

Why command source = terminal in both CDS, not BOP for the local case? The original question required that the Start/Stop push button initiate motion in both cases. A BOP-key start would not match this requirement. By keeping P0700[1] = 2, the operator's panel-mounted push buttons remain the run authority in local mode; only the setpoint source changes. This is the recommended architecture and is the one documented in the MM440 Operating Instructions for the dual-standby / manual-override case.

Step-by-Step Configuration Procedure

All parameter writes are performed from the BOP. Navigate to each parameter, press P, use the up/down arrow to edit, press P again to confirm.

Step 1 – Motor and Drive Identification

Set the standard motor commissioning parameters before enabling any CDS switching. These are not CDS-dependent and apply to both data sets.

1. P0100 = 0 – operation in Europe (50 Hz, kW)
2. P0205 = 1 – inverter application (constant torque, low overload)
3. P0300 = 1 – select induction motor
4. P0304 – rated motor voltage (V)
5. P0305 – rated motor current (A)
6. P0307 – rated motor power (kW)
7. P0308 – rated motor cos φ
8. P0309 – rated motor efficiency (%)
9. P0310 – rated motor frequency (Hz)
10. P0311 – rated motor speed (RPM)
11. P0335 = 1 – motor cooling = self-ventilated
12. P0640 = 150 – motor overload factor (%)
13. P1080 = 0 – global minimum frequency (Hz)
14. P1082 = 50 – global maximum frequency (Hz)
15. P1120 = 10 – ramp-up time (s)
16. P1121 = 10 – ramp-down time (s)
17. P1135 = 5 – OFF3 ramp-down time (s)
18. P1300 = 0 – V/f linear characteristic

Run quick commissioning by setting P0010 = 1 and then P3900 = 3 to calculate motor data automatically. After the drive returns to display mode, set P0010 = 0.

Step 2 – Configure the Command Source for Each CDS

1. P0700[0] = 2 – CDS0 commands come from the terminal strip.
2. P0700[1] = 2 – CDS1 commands also come from the terminal strip (keeps the operator push button active in local mode).

Step 3 – Configure the Setpoint Source for Each CDS

1. P1000[0] = 2 – CDS0 reads the main setpoint from analog input 1 (terminals 3 and 4, 0–10 V default; 4–20 mA if P0756 is re-scaled).
2. P1000[1] = 1 – CDS1 reads the main setpoint from the internal MOP, whose value is bumped by DIN2 (raise) and DIN3 (lower).

Step 4 – Map the Digital Inputs for Each CDS

Step 5 – Activate the CDS Selector on DIN4

1. P0810 = 4 – the bit-0 CDS selector source is connected to digital input 4.
2. Verify with r0050; bit 0 should follow the state of DIN4 in real time.

Step 6 – Configure the MOP Behavior in CDS1

1. P1031 = 1 – store last MOP setpoint so the drive resumes at the previously commanded speed after a power cycle.
2. P1032 = 1 – inhibit negative MOP setpoints (motor cannot run in reverse via MOP raise/lower).
3. P1040[1] = 40.0 – CDS1 MOP starting setpoint. The drive will ramp to 40 Hz on the first ON command in local mode, then accept raise/lower presses.
4. P1080[1] = 40.0 – CDS1 minimum frequency. The MOP cannot command below 40 Hz in local mode; the motor will not stall at low speed.
5. P1058[1] = 50.0 – CDS1 jog frequency (optional, used if a separate jog input is also wired).

Step 7 – Configure the Analog Input for CDS0

1. P0756[0] = 0 – ADC1 type = 0–10 V unipolar (default).
2. P0757[0] = 0 – ADC1 scaling x1 = 0 V.
3. P0758[0] = 0.0 – ADC1 scaling y1 = 0 %.
4. P0759[0] = 10.0 – ADC1 scaling x2 = 10 V.
5. P0760[0] = 100.0 – ADC1 scaling y2 = 100 %.
6. P0761[0] = 0 – ADC1 dead-band width = 0 V (no dead-band for PLC-driven setpoint).

The default 0–10 V to 0–50 Hz mapping is usually correct; if the PLC outputs 4–20 mA, wire to terminals 10/11 (ADC2) instead and re-scale P0756[1] = 2, P0759[1] = 20 mA.

Step 8 – Set Access Level and Save

1. P0003 = 3 – expert access level (required to see and edit P0100 and other expert-only parameters).
2. P0971 = 1 – save all parameters to EEPROM. The drive will copy RAM values to non-volatile memory; allow approximately 5 seconds for the operation to complete.

Terminal Wiring and I/O Assignment

The MM440 control terminals are located on the front, behind the front cover. Use the diagram below for a single-supply, sinking-input wiring scheme (24 V supplied from the MM440 internal +24 V on terminal 9):

Wiring notes:

• Use a single 24 V rail from pin 9 and run the Stop N.C. contact in series with all start devices. Pressing Stop must drop DIN1 regardless of the CDS selected.
• For DIN4 selector, route the same +24 V from pin 9 through the L/R switch directly to pin 8.
• ADC1 reference (pin 4) must be tied to pin 1 (DGND) for single-ended 0–10 V PLC output. If the PLC output is differential, leave pin 4 connected to the PLC negative terminal only.

MOP (Motor Potentiometer) Operation in CDS1

Once P1000[1] = 1, the setpoint displayed in r0021 is the MOP setpoint. It is calculated as:

f_setpoint = P1040[1] + MOP_increment × P1058 × dt

where MOP_increment is +1 when DIN2 is active, –1 when DIN3 is active, P1058 is the MOP ramp rate (Hz/s), and dt is the scan time. Typical tuning values:

The MM440 uses P1058/P1059 on MM440 ≥ FW 1.1; on older firmware the values P1060/P1061 control the rate. The Operating Instructions confirm which parameters apply to the firmware version on your nameplate label.

Analog Setpoint from PLC in CDS0

When DIN4 is LOW, CDS0 is active and r0021 reads the scaled value of ADC1 in percent. The MM440 multiplies this percentage by P2000 (default 50 Hz reference) to obtain the setpoint in Hz:

f_setpoint [Hz] = r0021 [%] × P2000 [Hz] / 100

If the PLC outputs 0–10 V, the resulting speed range is 0–50 Hz. If a different range is required, scale either P0757–P0760 (analog scaling) or P2000 (reference). Verify the scaling live with r0021 while the drive is stopped (no ON command), which avoids any setpoint filtering artifacts.

Commissioning and Verification

1. Power-on test: Energize the drive with the Start push button released and the L/R selector in Remote (LOW). BOP should show the drive in "Ready" (r0002 = 1) with output frequency 0 Hz.
2. Remote speed sweep: Press Start. Drive should accelerate to 0 Hz (PLC at 0 V). Command the PLC to 5 V. r0021 should read 50 %; r0024 should read 25 Hz within ramp time P1120.
3. Selector switch test: With the drive running at 25 Hz, flip the L/R switch to Local (HIGH). The MM440 should freeze the MOP setpoint at the value of P1040[1] (default 5 Hz, or whatever the MOP had stored), not the analog value. Output frequency should ramp to that MOP value using P1121.
4. Local speed sweep: Press MOP Raise for 5 s. r0024 should increase by approximately P1058 × 5 = 25 Hz from the starting value (subject to P1082 clamp).
5. Stop authority: Press Stop. Drive should ramp down per P1121. Toggle L/R switch back to Remote, then to Local again. Drive should remain stopped; the MOP setpoint persists per P1031 = 1.
6. Fault injection test: Open the motor wiring at the drive output terminals and command a run. The drive should trip with F0001 (overcurrent). Acknowledge via DIN5; drive should return to ready.

Troubleshooting Matrix

For any of the above, the canonical reference is the MM440 parameter list and fault code table in the Operating Instructions (Section "Faults and Alarms").

Field-Proven Caveats

• Parameter changes are written to RAM immediately but lost on power-down unless P0971 = 1 is executed. Always run a final save before closing the cabinet.
• The CDS switch is bumpless only for the setpoint path. If the drive is at 50 Hz (analog) and you switch to local, the output ramps to the MOP value via the deceleration ramp; it does not jump. This is the expected and safe behavior.
• When both CDS use the same P0700 value (terminal), changing the active CDS mid-run does not interrupt the run command. This is why this architecture is preferred over a P0700 toggle.
• Some PLC scan schedules expect a feedback bit that confirms the active CDS. Map r0050 bit 0 to a digital output using P0731 or expose it over USS to the PLC if the L/R status is needed by the automation.

FAQ