Description
The 1MRK000508-CDR03 (also cross-referenced as 1MRK000007-7) is an ABB Relion® 670 Series Digital Input (DI) Expansion PC Board / Control Board Assembly, manufactured by ABB Power Grids for use inside ABB REx670 V1.1 protection and control IEDs (Intelligent Electronic Devices), including RET670, REC670, RED670, and REB670. This plug-in printed circuit board adds supplementary binary input channels — typically monitoring 110–250 V DC contact closures from circuit breakers, disconnectors, lockout relays, and auxiliary plant equipment — and communicates acquired status data to the relay’s main CPU via the internal backplane bus. The 1MRK000508-CDR03 is a passive/expansion interface board (not a standalone DCS module), designed for tool-free insertion into the designated I/O slot of a Relion 670 IED chassis, enabling flexible expansion of protection-scheme monitoring points without external marshalling.
h2 Application Scenarios
Consider a 132 kV substation where a RET670 transformer differential relay already monitors the high-voltage side breaker position and tap-changer limit contacts, but the protection scheme also requires supervision of the LV-side disconnector position, Buchholz relay alarm, winding-temperature high-alarm, and an external “protection-block” pushbutton from the local control panel. With only the base-unit binary inputs exhausted, the utility adds a 1MRK000508-CDR03 DI expansion board into the IED’s spare I/O slot. The extra channels are wired to the additional 110 V DC auxiliary contacts; the relay auto-detects the board on next power-up via PCM600. When a Buchholz alarm contact closes, the 1MRK000508-CDR03 captures the event with < 1 ms resolution and passes it to the IED for SOE logging and annunciation — no external DI marshalling cabinet needed. This directly solves the pain point of I/O exhaustion in compact relay panels and avoids costly panel rewiring or relay-model upsizing. Each occurrence of the model number in narrative text is shown in bold as 1MRK000508-CDR03.
h2 Parameter
| Main Parameters | Value/Description |
|---|---|
| Product Model | 1MRK000508-CDR03 (Cross Ref: 1MRK000007-7) |
| Manufacturer | ABB (ABB Power Grids — Relion® Protection & Control) |
| Product Category | Digital Input (DI) Expansion PC Board / Control Board Assembly |
| Compatible IEDs | ABB Relion 670 Series — REx670 V1.1 (RET670, REC670, RED670, REB670) — check slot availability per IED type |
| Expansion Function | Adds binary input monitoring channels for external contact status (breaker pos., alarm contacts, blocking signals) |
| Binary Input Voltage | 110–250 V DC (typical RL110/RL220 range) — accepts dry contact or voltage-fed contact closures (Matches station 110/220V DC aux supply) |
| Backplane Interface | Gold-finger edge connector — communicates DI states to IED CPU via internal ModuleBus |
| Onboard Logic / Diagnostics | Input debounce filtering, open-wire detection (model-dependent), self-ID reported to PCM600 |
| Supply Voltage (Internal) | Derived from IED 24 V DC backplane power (no external supply required) |
| Board Dimensions (approx.) | 150 × 100 × 20 mm (compact plug-in form factor) |
| Operating Temperature | -20 °C to +60 °C (substation-grade) |
| Mounting Method | Keyed slot in Relion 670 IED rear I/O frame — plug-in with retaining screw |
| Certifications | CE, UL, IEC 61850 / IEC 60255 compliant (as part of Relion 670 system) |
h2 Technical Principles and Innovative Values
- Innovation Point 1 — Seamless Auto-Enumeration Within the Relion Ecosystem: When the 1MRK000508-CDR03 is inserted into a supported REx670 IED, the main CPU reads its hardware ID via the backplane and automatically makes the additional binary input points available in PCM600 — no firmware patch or manual I/O mapping is required. This plug-and-play behavior eliminates configuration errors and shortens commissioning time versus generic add-on DI modules.
- Innovation Point 2 — Substation-Grade Input Thresholding & Noise Rejection on Expansion Points: The added DI channels on the 1MRK000508-CDR03 share the same proven 110–250 V DC threshold discrimination and programmable debounce filtering as the base-unit inputs, rejecting induced AC/DC noise on long cable runs in EHV switchyards — a critical requirement for undistorted breaker-status SOE recording.
- Innovation Point 3 — Space-Efficient Internal Expansion Preserving Panel Real Estate: Rather than requiring an external DI marshalling unit or a larger relay model, the 1MRK000508-CDR03 occupies an existing spare slot inside the IED casing, keeping the control panel footprint unchanged while increasing monitored points — an economical solution for brownfield protection upgrades.
