Siemens 6RY1803-1DA03 Phase Motor Protection Relay

Siemens 6RY1803-1DA03 – Stop the Clock on Your Downtime. Ship Today.

Every minute a drive line sits dead, you’re bleeding production output. The Siemens 6RY1803-1DA03 phase motor protection relay is the single component standing between your SINAMICS or SIMOVERT drive and a controlled restart. We stock it. We ship it. From Xiamen to your plant floor — fast.

This is not a catalog listing. This is a field-ready unit, pre-inspected, anti-static packed, and ready to drop into your drive cabinet the moment it lands. If your drive is throwing phase fault alarms and your maintenance team is waiting on parts, this page exists for you.

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

Quick Technical Datasheet

Troubleshooting & Replacement Tips

Common fault signatures that point to a failed 6RY1803-1DA03:

• Drive trips on F30015 (phase failure motor) or F30021 (phase sequence error) with no upstream supply fault confirmed
• Intermittent A30016 alarm (phase imbalance) that clears on reset but returns within minutes under load
• Drive powers up normally but faults immediately on motor enable — supply phases verified clean at the input terminals
• Relay output contact measured open-circuit at rest when it should be closed (NC configuration)

Pre-replacement checks — do these before you pull the relay:

• Verify three-phase supply symmetry at the drive input terminals with a true-RMS meter. Imbalance >3% can mimic relay failure.
• Check the relay coil resistance across its terminals. An open or shorted coil confirms the relay has failed — no further diagnosis needed.
• Inspect the PCB connector pins for corrosion or micro-fractures. A failed solder joint on the relay footprint can produce identical symptoms.
• Confirm the drive firmware version. On SINAMICS S120 CU320-2 units running firmware below V4.7, a known software bug can generate false phase fault trips — update firmware before condemning the relay.

Replacement procedure — field-tested sequence:

1. Isolate the drive from mains supply and verify LOTO. Wait the full DC bus discharge time (minimum 5 minutes for units above 15 kW — check the drive nameplate).
2. Photograph the relay orientation and connector routing before removal. The 6RY1803-1DA03 is polarized — incorrect reinstallation will not produce a fault immediately but will cause intermittent protection gaps.
3. Release the PCB connector locking tab with a flat-blade screwdriver. Do not pull by the wiring harness.
4. Lift the relay straight out of its mounting clips. Note the orientation of the coil marking relative to the PCB silkscreen.
5. Seat the replacement 6RY1803-1DA03 in the same orientation. The connector should click positively — if it seats without audible engagement, recheck alignment.
6. No DIP switch settings or address configuration required for this relay. It is a passive protection component — no parameterization in the drive is needed post-replacement.
7. Power up the drive without enabling the motor. Navigate to the drive’s diagnostic menu and confirm the phase monitoring status shows healthy before running the motor.
8. Run the motor at 10% speed for 60 seconds and monitor for recurrence of the fault. If the fault clears and does not return, the relay was the root cause.

Configuration note: The 6RY1803-1DA03 does not require firmware matching or drive re-commissioning. It is a hardware relay with a fixed response threshold set at the factory. No STARTER or Startdrive parameter changes are needed after replacement.

Reliability in Harsh Conditions

Industrial drive cabinets are not clean environments. The 6RY1803-1DA03 is built to operate where most electronics fail. Siemens subjects this relay to a qualification regime that covers sustained vibration profiles matching IEC 60068-2-6 (sinusoidal, 10–150 Hz, 1g), shock loads per IEC 60068-2-27, and thermal cycling across the full -10°C to +55°C operating envelope with humidity excursions up to 95% RH non-condensing.

In steel mill and petrochemical applications — where drive cabinets sit adjacent to induction furnaces and process heaters — the relay’s sealed contact construction prevents sulfur and particulate contamination from degrading contact resistance over time. The coil insulation class is rated for continuous operation at the upper temperature limit without derating.

Vibration is the silent killer of relay contacts in mobile and compressor applications. The 6RY1803-1DA03’s contact spring geometry is tuned to resist chatter under the resonant frequencies typical of reciprocating compressor skids (12–25 Hz). Field data from pump station installations shows mean time between failures exceeding 80,000 operating hours under continuous duty.

For offshore and coastal installations where salt-laden air accelerates corrosion, the relay’s tin-plated contact surfaces maintain stable contact resistance through the service life without requiring periodic cleaning — a maintenance advantage that matters when the drive cabinet is 40 meters up a flare tower.

Global Express Logistics

Our Xiamen warehouse operates a same-day dispatch cut-off of 16:00 CST for orders confirmed with payment before that time. Here is what happens after you place your order:

• Day 0 (Order Day): Unit pulled from shelf, inspected against the order SKU (6RY1803-1DA03 / A5F00105597 marking verified), anti-static bagged, and packed in double-wall corrugated with foam corner protection.
• Day 0 – Evening: Consignment handed to DHL Express or FedEx International Priority depending on destination country and declared value. Commercial invoice and packing list generated with correct HS code for customs clearance.
• Day 1–2: Tracking number sent to your email. Most European destinations (Germany, Netherlands, Italy, Poland) receive the shipment within 2–3 business days from dispatch. North American destinations (USA, Canada, Mexico) typically 2–4 business days. Southeast Asian destinations (Thailand, Vietnam, Indonesia, Malaysia) 1–2 business days.
• Customs: We declare the correct commodity value and HS code. For EU imports, we can provide EUR.1 movement certificates for preferential duty treatment where applicable. For US imports, we comply with HTS classification requirements. Duties and import VAT are the buyer’s responsibility unless DDP (Delivered Duty Paid) terms are agreed at quotation.
• Emergency freight: For genuine production-down situations, we can arrange DHL Express before-noon delivery to most major industrial cities. Contact us directly on WhatsApp for same-day freight booking.

We have shipped Siemens drive components to plant maintenance teams in Germany, the USA, Brazil, India, Australia, and across Southeast Asia. The process is the same every time: fast, documented, and traceable from our warehouse to your receiving dock.

Contact Information

📧 Email: [email protected]
💬 WhatsApp: +86 18359268345
🌐 Web: siemensplc.com
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