Siemens 6EP1964-2BA00 Redundancy Module

SIEMENS 6EP1964-2BA00 – Stop the Clock on Downtime: SITOP Redundancy Module, Stocked and Ready

Every minute a production line sits idle costs money — sometimes thousands of dollars per hour in lost throughput, emergency labor, and contractual penalties. When a SITOP power supply fails and there is no redundancy module in the cabinet, the entire 24 VDC bus collapses: PLCs drop out, field devices lose power, and safety systems trigger emergency stops. The SIEMENS 6EP1964-2BA00 is the hardware that prevents that cascade. It sits between two parallel SITOP power supply units, actively balancing load and executing a sub-millisecond failover the moment one PSU drops below threshold — no PLC intervention, no operator action, no interruption to the process.

We stock the 6EP1964-2BA00 in Xiamen, China, and ship globally via DHL Express and FedEx International Priority. If your line is down today, contact us now — we can have a unit moving within hours of order confirmation.

URGENT REQUIREMENT? Contact: [email protected] | WhatsApp: +86 18359268345

Quick Technical Datasheet

Troubleshooting & Replacement Tips

Common failure symptoms that point to the 6EP1964-2BA00:

• Both SITOP PSUs are powered and showing green LEDs, but the 24 VDC bus voltage is sagging or unstable — the redundancy module’s internal MOSFET stage may have failed open, causing one PSU to back-feed into the other.
• The fault relay output is permanently energized (or permanently de-energized, depending on wiring convention) even though both PSUs appear healthy — the module’s internal comparator circuit has likely lost reference.
• Intermittent PLC I/O dropouts during peak load cycles, with no PSU fault LED — the module’s current-sharing logic is no longer balancing load, causing one PSU to hit its current limit while the other runs light.
• Visible burn marks or discoloration on the terminal block side of the module — typically caused by a sustained overcurrent event on one PSU leg.

Step-by-step replacement procedure:

1. Isolate safely. Before touching any wiring, de-energize both SITOP PSUs at their AC input breakers. Verify 0 VDC on the 24 V bus with a calibrated multimeter. Do not rely on the PSU’s own LED — a failed redundancy module can hold residual charge on the output bus.
2. Document terminal wiring. Photograph or sketch the existing wiring on terminals L+, M, and the relay output before disconnecting. The 6EP1964-2BA00 uses a straightforward 4-terminal layout, but polarity errors on the relay output will invert your fault logic in the PLC.
3. Remove the failed module. Loosen the DIN rail locking tab and slide the module off. Inspect the DIN rail segment for heat damage — a failed module running hot can warp the rail and cause poor contact with the replacement.
4. No DIP switches or address configuration required. The 6EP1964-2BA00 is a passive-active hybrid device with no firmware, no address settings, and no commissioning software. It is plug-and-play within the SITOP family — wire it in, power up, and verify the green status LED illuminates within 2 seconds of both PSUs reaching nominal voltage.
5. Verify load sharing after power-up. With both PSUs energized and the new module installed, measure the output current of each PSU individually using a clamp meter. Under normal load, each PSU should carry approximately 50 % of the total bus current (±10 %). A significant imbalance indicates a wiring error or a fault in one of the PSUs, not the redundancy module.
6. Test failover. With the system running at normal load, manually trip one PSU’s AC input breaker. The bus voltage should not dip below 22.8 VDC (5 % below nominal) during the switchover. If it does, check the cable cross-section between the PSU output terminals and the redundancy module — undersized wiring adds resistance that amplifies the voltage dip during current transfer.
7. Confirm relay output logic in PLC. After restoration, force a simulated fault and verify that the PLC receives the correct diagnostic signal. Update the maintenance log with the replacement date and the serial number of the new module.

Firmware note: The 6EP1964-2BA00 contains no user-programmable firmware. There is no STEP 7 or TIA Portal configuration required. If your system uses a SITOP UPS module (e.g., 6EP4134-3AB00) in the same cabinet, that UPS module has its own firmware — ensure it is on a compatible version per the SITOP system manual A5E00298289 before commissioning the replacement redundancy module.

Reliability in Harsh Conditions

The 6EP1964-2BA00 is not a general-purpose power accessory — it is built to the same environmental specification as the SITOP PSU family it supports, which means it is validated for continuous operation in conditions that would degrade consumer-grade electronics within weeks.

Thermal performance: The module’s internal MOSFET switching stage is rated for junction temperatures up to 125 °C, with the housing designed to dissipate heat passively across the full −25 °C to +70 °C ambient range. In practice, this means the module can operate in an unventilated steel enclosure on a summer production floor without thermal throttling or derating.

Vibration and shock: Tested to IEC 60068-2-6 (sinusoidal vibration, 10–150 Hz, 1 g) and IEC 60068-2-27 (mechanical shock, 15 g / 11 ms half-sine). The DIN rail mounting mechanism uses a spring-loaded locking tab that maintains positive contact under continuous vibration — relevant for installations near compressors, presses, or mobile equipment.

Humidity and condensation: Rated to 95 % relative humidity, non-condensing. The PCB conformal coating provides additional protection against moisture ingress in environments with rapid temperature cycling — common in food processing plants where washdown procedures cause localized condensation inside control cabinets.

EMC immunity: Compliant with EN 61000-6-2 (industrial immunity standard), including 4 kV contact discharge (ESD), 2 kV fast transient burst on signal lines, and 10 V/m radiated field immunity. In practice, the module has been deployed in arc furnace control rooms and high-frequency drive environments without spurious fault relay trips.

Global Express Logistics

Our warehouse is located in Xiamen, Fujian Province, China — one of the country’s primary export hubs with direct access to Xiamen Gaoqi International Airport and Xiamen Port. This geographic position allows us to consolidate shipments and hand off to DHL Express or FedEx International Priority within the same business day for orders confirmed before 15:00 CST.

Typical transit times from Xiamen:

• Southeast Asia (Singapore, Thailand, Malaysia, Vietnam): 2–3 business days via DHL Express
• Europe (Germany, Netherlands, Poland, UK): 3–5 business days via FedEx International Priority
• North America (USA, Canada, Mexico): 3–5 business days via DHL Express Worldwide
• Middle East (UAE, Saudi Arabia, Qatar): 3–4 business days via FedEx International Priority
• South America (Brazil, Chile, Argentina): 5–7 business days via DHL Express
• Australia & New Zealand: 3–4 business days via DHL Express

Every shipment includes a commercial invoice, packing list, and certificate of origin. For customers requiring customs pre-clearance documentation (e.g., HS code 8504.40 for power supply modules), we prepare and transmit all paperwork electronically before the shipment departs. Tracking numbers are issued within 2 hours of carrier pickup and sent directly to your registered email address.

For urgent air freight requirements — including same-day dispatch for orders confirmed before noon CST — contact our logistics team directly via WhatsApp. We can also arrange door-to-door delivery with customs brokerage included for customers in the EU, USA, and Australia.

Contact Information

Email: [email protected]
WhatsApp: +86 18359268345
Web: siemensplc.com
Location: Xiamen, China
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