Product Overview

The 6ES7132-6GD51-0BA0​ is a Siemens SIMATIC ET 200SP Signal Relay Module, product-designation RQ CO 4× 24 V DC/2 A ST​ — a 4-channel digital output slice that drives electromechanical relay changeover (CO / SPDT) contacts from the ET 200SP backplane. It belongs to the ET 200SP digital-output (DQ) family and is the changeover sibling of the RQ NO variant (6ES7132-6BD51-0BA0); the “-GD51” code pins “G = relay CO, D = 4-channel, 51 = ST grade.” Where a semiconductor DO slice (e.g. 6ES7132-6BH00, 8× 24 V DC/0.5 A) can only switch low-voltage DC loads, the 6ES7132-6GD51-0BA0​ uses isolated relay contacts that can break up to 250 V AC / 30 V DC on the load side while the coil is driven from the ET 200SP’s 24 V DC electronics supply — making it the go-to ET 200SP slice for switching 230 V AC indicating beacons, small contractor coils, alarm horns, solenoid interlocks, and any “signal-grade” AC load that a solid-state DO can’t touch.Physically, the 6ES7132-6GD51-0BA0​ is the classic ET 200SP skinny profile: 15 mm wide, 73 mm high, 58 mm deep, ~30 g, snapping directly onto a BU-type A0 BaseUnit behind an IM 155-6 PN (or DP) interface module. The A0 BU carries the push-in terminal rows for the four CO contacts (COM/NO/NC per channel) and the 24 V coil feed; the module itself carries only the relay ASIC, coil drivers, channel isolation, and the diagnostic/LED circuitry. Colour Code CC00​ (black/white label) identifies it as the RQ CO 4× ST type on the BU — important when a rack mixes multiple DQ slices, because ET 200SP uses colour-coded “slot-proofing” so a technician can’t accidentally seat a BH (8× DC) where a GD (4× relay CO) belongs. The 6ES7132-6GD51-0BA0​ draws ~50 mA from the ET 200SP backplane 5 V (well within the IM 155-6’s budget) and ~1.2 W typical coil burden. Diagnostics cover module-level supply-voltage monitoring (green/red DIAG LED, SF/ON) and per-channel status LEDs; substitute-value output is supported — if the IM loses PROFINET, the 6ES7132-6GD51-0BA0​ can hold last-state or a preconfigured substitute per channel, preventing a relay flap on a comms glitch.In the automation hierarchy, the 6ES7132-6GD51-0BA0​ hangs off an IM 155-6 PN (or HS/DP) in an ET 200SP node — the node itself is a PROFINET device under an S7-1500/1200 PLC or a PCS 7/WinCC OA host. Common pairings: IM 155-6 PN ST (6ES7155-6AU01-0BN0) + BU A0 + 6ES7132-6GD51-0BA0​ + a few DI/AI slices, all on a 15 mm–wide DIN string that fits a 200 mm cabinet width where an ET 200S or S7-300 rack would never fit. Unlike the earlier entries (SICOMP, LOGO! 0BA1, S7-200) which are all obsolete/discontinued, the 6ES7132-6GD51-0BA0​ is active catalog​ (PLM PM300: Active per Siemens mall), though standard lead time ex-works is quoted ~70 days in some regions — so MRO buyers still keep NOS/cold-spares for critical lines.One reseller-pollution warning before diving deeper: many listings conflate the 6ES7132-6GD51-0BA0​ with the older ET 200S relay modules (6ES7 132-4BD00/4GD00 — those are the chunky 80 mm wide ET 200S slices with screw-terminal headers, not ET 200SP 15 mm push-in). Also, “signal relay” sounds like it might be solid-state or a “signal conditioning” module — it’s not; it’s electromechanical relay DO with CO contacts, 2 A signal-grade load. If your load is >2 A or motor-starting (AC-3), you derate to 0.5 A per the datasheet — or move the contactor coil upstream and let the 6ES7132-6GD51-0BA0​ drive an interposing relay instead.

Technical Specifications