GE IC3600KRSV1 Speed Sense & Overspeed Trip Card

Description

In high-stakes industrial control environments, the reliability of every speed feedback signal is non-negotiable. Turbine control systems, large compressor drives, and generator excitation circuits all depend on rock-solid tachometer or encoder inputs to maintain precise rotational speed regulation. When a single dropped pulse or electrical transient corrupts the feedback loop, the consequences range from protective trips that shut down an entire unit to catastrophic overspeed events that destroy equipment. Older analog speed cards and basic frequency-to-voltage converters simply lack the noise immunity, resolution, and diagnostic depth required in modern turbine control retrofits or legacy GE Mark I/II systems that must stay online for decades.

This is precisely the challenge the GE IC3600KRSV1 was built to eliminate. As the dedicated speed sensing and overspeed trip card for the Speedtronic™ Mark I and Mark II turbine control series, the IC3600KRSV1 accepts direct magnetic pickup inputs from 1 Hz to 10 kHz, converts them instantly to a clean 0–10 V speed signal, and simultaneously provides three independent, hardware-based overspeed trip relays. Engineers upgrading or maintaining gas turbine packages choose the IC3600KRSV1 when they need absolute confidence that speed feedback will remain accurate and trip circuits will actuate within milliseconds—even in the presence of severe electrical noise, voltage spikes, or pickup cable faults common in power generation environments.

The GE IC3600KRSV1 solves a problem that has plagued many aging Speedtronic installations: false trips caused by noisy pickups or outright failure to trip due to degraded older cards. With fully isolated inputs, adjustable pickup threshold pots, and triple-redundant trip contacts voted 2oo3 internally, it delivers the kind of high-reliability overspeed protection that regulatory bodies and insurers expect in critical turbine applications.

The IC3600KRSV1 lives in the core Speedtronic card rack, typically occupying one of the dedicated speed input slots directly behind the Mark I/II regulator card (IC3600SRDF or SRDE). It accepts up to three magnetic pickups (usually 60-tooth wheels) through front-accessible barrier terminals, conditions the raw sine-wave signals with high-impedance amplifiers, and squares them into clean pulses for the internal frequency counter. The onboard microprocessor (for its era) calculates shaft RPM with 0.1 % accuracy and drives a buffered 0–10 V analog output that feeds the main speed control loop.

What sets the card apart in real systems is its hardware trip logic: three separate overspeed comparators monitor frequency independently and energize (or de-energize, depending on jumper settings) heavy-duty relays rated for 10 A at 125 VDC. These contacts wire directly into the fuel/stop valve trip circuit and emergency trip header, bypassing all software so that a trip occurs even if the main CPU fails. On-card test points and a built-in frequency generator allow technicians to inject simulated signals during commissioning or annual validation without removing the card or disturbing field wiring. In Mark II systems with dual redundant speed channels, two IC3600KRSV1 cards are typically installed and voted externally to achieve true 2oo3 overspeed protection.

Deploying the GE IC3600KRSV1 gives you the peace of mind that comes from hardware-enforced overspeed protection that has been field-proven on thousands of Frame 3, 5, 6, and 7 turbines since the 1970s. The triple-redundant trip relays and isolated inputs dramatically reduce nuisance trips caused by ground noise or lightning-induced transients—issues that routinely plague single-channel or non-isolated speed cards. Plants report that swapping older IC3600SRSx or IC3600SRSA cards for the IC3600KRSV1 often cuts speed-related alarms by more than 80 % while simultaneously improving trip reliability during actual overspeed tests.

Maintenance teams value the on-card frequency calibration source and clearly labeled test points, which turn a once-dreaded overspeed trip validation into a 30-minute procedure instead of a multi-hour outage. Because the card uses the same edge connector and mounting footprint as earlier speed cards, retrofitting is typically a drop-in evolution that requires no rack modifications and minimal re-wiring.

You’ll find the IC3600KRSV1 at the heart of nearly every operating GE heavy-duty gas turbine with legacy Mark I or Mark II controls—particularly Frame 5, Frame 6B, and Frame 7EA units in combined-cycle power plants, pipeline compressor stations, and mechanical-drive applications in refineries. It is the standard choice when performing life-extension upgrades on 1970s–1980s packages that must meet modern insurance and ISO 21789 overspeed protection requirements without replacing the entire control system. In marine propulsion and test-stand environments where vibration exceeds 5 g and continuous operation is measured in years rather than hours, the IC3600KRSV1 continues to deliver the critical system uptime that operators demand.

IC3600KRSV2 – Updated revision with enhanced EMI filtering for offshore platforms

IC3600SRDF9 – Companion regulator card often paired in Mark II dual-channel setups

IC3600SRSB1 – Earlier single-trip version (replace with KRSV1 for redundancy)

IC3600QOXA – Overspeed test panel interface module used during validation

IC3600VMPA1 – Magnetic pickup preamplifier for very low-amplitude signals (<1 V p-p)

44A294568-G01 – Complete rack wiring harness for three-pickup configurations

DS3820VSNA – Speedtronic Mark IV-era equivalent (migration path for full upgrade)

Before installing or replacing an IC3600KRSV1, verify that the new card’s revision matches your existing trip setpoint jumpers (usually factory-set to 110 % for gas turbines) and that the rack supplies clean 24 VDC within ±5 %. Check magnetic pickup gap (0.015–0.025 in) and cable shielding continuity—poor shielding is the leading cause of erratic speed readings after card replacement. If you’re moving from an older SRSx card, transfer the three calibration pots’ settings or re-calibrate using the on-card oscillator and a frequency counter to match previous behavior exactly.

In service, periodic checks are straightforward: confirm pickup voltage at the front test points (>2 V p-p at rated speed) and exercise the built-in trip test switch during each outage. Relay contacts rarely fail, but a quick continuity check across the three trip circuits once a year satisfies most insurance auditors. GE still stocks and repairs these cards through their Turbine Control Services group, so turnaround is typically under two weeks even for rush jobs.