ABB Emax 2 Ekip Trip Unit Alarm Codes and Fault Diagnosis Guide
What is an ABB Emax 2 Ekip trip unit alarm code? An ABB Emax 2 Ekip trip unit alarm code is a diagnostic identifier generated by the Ekip protection module — covering breakers rated 400–6300 A under IEC 60947-2 — that flags overload, short-circuit, ground fault, or internal hardware conditions before or after a trip event. Misreading an L, S, I, or G code as a nuisance trip rather than a legitimate fault condition can lead to repeated resets on a degraded circuit, masking load imbalances or insulation failures that escalate into busbar damage. This guide covers Ekip fault-reporting architecture, field-encountered alarm codes with threshold parameters, a structured step-by-step diagnostic procedure, long-time protection curve mathematics, false-trip discrimination methods, and diagnostic data availability across Ekip variants.
How the Ekip Trip Unit Reports Faults: Architecture Before Codes
Before reading any code on an ABB Emax 2, you need to understand what is generating it. The Ekip trip unit is not a simple bimetallic relay. It is a microprocessor-based protection and measurement device with three independent display layers: the front-panel LEDs (L, S, I, G, plus warning and alarm), the LCD or TFT screen, and the event log accessible through Ekip Connect over the front Bluetooth/USB or rear Modbus/Profibus/IEC 61850 communication module.
In our experience, junior technicians read only the LEDs and miss two-thirds of the diagnostic information. A trip caused by a transient on phase L2 may show only the "I" LED, while the event log records the actual peak current, the time-to-trip in milliseconds, the phase involved, and any warnings that preceded the event by hours or days. Always pull the event log first.
The Emax 2 platform offers Ekip variants from the basic Ekip Dip (mechanical-style dial settings, found on units like the ABB 1SDA070701R1 E1.2B 630 Ekip Dip LI) up to Ekip Touch and Ekip Hi-Touch with full TFT, oscillography and harmonic analysis. The diagnostic philosophy is identical across the range, but the depth of data you can extract scales with the trip unit class. For a wider feature comparison, see What Is the ABB SACE Emax 2? Features, Models and Key Benefits.
Detailed protection settings, alarm code definitions and Ekip trip unit diagnostic procedures for the ABB Emax 2 are documented in the manufacturer's official technical literature, available via the ABB Emax 2 product documentation portal.
The Core Alarm Codes Engineers Encounter in the Field
ABB groups Ekip messages into three severities: information (white/blue), warning (yellow), and alarm/trip (red). The codes you see on the display use a short mnemonic plus a numeric reference. Here is what you will actually meet on a working switchboard.
Protection trip codes (the breaker has opened)
L — Long-time overload. Triggered when I>I1 for longer than the t1 curve allows. In a paper mill we serviced last year, an 800 A feeder on an ABB 1SDA070741R1 E1.2B 800 was tripping every Tuesday at 14:00. The L LED was lit; the event log showed sustained 920 A for 480 s. Root cause: a chiller compressor staged in alongside the morning shift load. Solution was load shedding via Ekip Signalling 4K, not a higher I1 setting.
S — Short-time delay trip. I>I2 for t2. Common on motor groups during reacceleration after a voltage dip. If S trips repeatedly without a real fault, check the I²t selectivity setting against the downstream MCCB.
I — Instantaneous trip. I>I3, no intentional delay. This is your hard short circuit signature. Always inspect cables and downstream gear before reclosing.
G / Gext — Ground fault (internal CT sum or external toroid). Below 1200 A typical setting on a 1600 A frame. False G trips on TN-S systems are usually caused by a parallel neutral-to-earth bond downstream — the classic mistake of bonding N to PE in a sub-distribution board.
Iinst — Self-protection instantaneous trip. The unit detected a current above its withstand and tripped without using the I curve. Treat the breaker as suspect: inspect contacts, measure contact resistance with a micro-ohmmeter, and verify Icw before re-energising.
Rc — Residual current trip (only with Ekip Rc module fitted). Reports the leakage current value at trip. Anything above 30 mA on a healthy industrial feeder indicates insulation deterioration worth investigating.
Warnings and pre-alarms (breaker still closed)
These are the codes that tell you a trip is coming if you do nothing.
PR.A — Pre-alarm long-time, typically at 90% of I1. HI.A — High current warning, configurable. Tmax — Internal Ekip temperature exceeded (usually >85 °C). Ulow / Uhigh — Voltage outside protection thresholds (Ekip Measuring or higher). F.low / F.high — Frequency outside band, common on generator changeovers.
Self-diagnostic codes (the trip unit itself has a problem)
Per IEC 60947-2 Annex F, an electronic trip unit must self-monitor. The Ekip family reports:
ROM/RAM/EEPROM error — firmware or memory corruption. The breaker reverts to a hardware-protected mode and the alarm LED flashes. Replace the trip unit. Trip coil fault — the unit cannot verify continuity of the YO trip coil. Rating plug missing/wrong — In rated current selector not detected. Battery low — Ekip backup battery (CR2032 or external) below threshold; protection still works, but the local display goes dark when the breaker is open.
A Structured Diagnostic Procedure That Actually Works
Here is the sequence we use on industrial sites for any ABB Emax 2, regardless of which Ekip variant is fitted. It is boring. It is also reliable.
Step 1: Do not reclose. Tag out, then walk to the breaker.
Step 2: Photograph the LEDs and display before pressing iTest. Some warning indicators clear automatically after acknowledgement.
Step 3: Connect Ekip Connect via the front test connector. Export the last 200 events. The CSV will show timestamp, event type, phase, RMS current, peak current, time-to-trip and any concurrent warnings.
Step 4: Correlate with upstream measurements. Compare against the SCADA or power meter on the same bus. A real overload will be visible in the trend. A spurious trip will not.
Step 5: Insulation and continuity tests downstream if I, Iinst or G was reported. Use a 1000 V insulation tester per IEEE 43-2013 guidance for rotating machinery, or 500 V for general distribution per IEC 60364-6.
Step 6: Verify trip unit health. Run the auto-test (iTest button held 3 s) and check the trip-coil-continuity result. On Ekip Touch, navigate to Service → Self-test.
Step 7: Check settings against the protection coordination study. Engineers often overlook this — someone may have changed I1 or t2 during commissioning and never updated the relay coordination drawing.
Reading the Long-Time Curve: The Math Behind the L Code
On the ABB Emax 2, the L protection follows a thermal-memory I²t curve. When the L LED lights and the log reports a long-time trip, the time-to-trip should match the formula below within ±20% (IEC 60947-2 tolerance for class A trip units).
Formula: Long-time inverse trip time — Source: IEC 60947-2:2019 Annex F, Clause F.5.2 (trip unit characteristic)
tL = (t1 × (6 × I1)²) / I²
| Symbol | Description | Unit |
|---|---|---|
| tL | Trip time at measured current | s |
| t1 | Set time at 6 × I1 (Ekip parameter) | s |
| I1 | Long-time pickup setting | A |
| I | Measured RMS current | A |
Why this matters in diagnosis: if a 1000 A breaker (ABB 1SDA070781R1 E1.2B 1000) with I1 = 0.9 (so 900 A) and t1 = 12 s trips at a logged 1100 A in 25 s, that is consistent with the curve. If it tripped in 4 s, the trip unit is misbehaving — replace it.
Common False Trips and How to Distinguish Them From Real Faults
In practice, roughly 30% of Emax 2 trips reported to us turn out to be application or configuration issues rather than equipment faults. We covered the broader topic in ABB Emax 2 Nuisance Tripping: Root Causes, Diagnostic Steps and Fixes, but here are the diagnostic shortcuts.
Harmonics on VFD-fed loads
Modern variable frequency drives produce significant 5th and 7th harmonic currents. The Ekip Touch measures true RMS, so the L protection sees the real heating current — but if your protection coordination study used fundamental-only values, you will under-set I1. A common mistake is specifying a 1250 A breaker (ABB 1SDA070821R1 E1.2B 1250) for a 1100 A drive load and seeing nuisance L trips because the THD pushes RMS to 1180 A.
Inrush on transformer energising
A 1600 kVA dry-type transformer can draw 12–15× FLA for the first 2–3 cycles. If I3 is set below this peak, you get an instantaneous trip on every closing. The fix is either raising I3 (verify against downstream Icc) or using the Ekip "make current release" with a 5-cycle bypass.
Neutral overload on triplen-harmonic loads
On 4-pole Emax 2 frames with N protection enabled, the neutral can carry 1.7× the phase current under heavy 3rd harmonic. Setting INc = 100% (instead of the default 50%) is mandatory for IT data centre feeders — see ABB Emax 2 in Data Centers: MDB Design, Redundancy and Uptime Considerations.
Comparing Ekip Variants: What Diagnostic Data You Get
Procurement teams specifying the ABB Emax 2 often ask whether the Ekip Dip is "good enough" or whether the upgrade to Touch is justified. The answer depends on how much downtime a misdiagnosed trip costs you. For a critical 2000 A bus on an ABB 1SDA071021R1 E2.2B 2000, we always specify Touch or Hi-Touch.
| Diagnostic feature | Ekip Dip | Ekip Touch | Ekip Hi-Touch |
|---|---|---|---|
| Protection LEDs (L/S/I/G) | Yes | Yes | Yes |
| Event log depth | 20 events | 200 events | 200 events + 30 oscillographs |
| RMS metering | No | Yes (V, I, P, Q, S, PF) | Yes + harmonics to 50th |
| Ekip Connect (USB/Bluetooth) | Yes | Yes | Yes |
| Waveform capture | No | No | Yes (pre/post trip) |
| Communication options | Modbus RTU (optional) | Modbus, Profibus, IEC 61850 | All + redundant Ethernet |
| Typical use case | Sub-distribution feeders | Main incomers, motor groups | Generator paralleling, data centres |
For a deeper specification breakdown, the article ABB Emax 2 Full Technical Specifications lists the rated currents, breaking capacities and dimensions across the E1.2 to E6.2 family.
Maintenance Practices That Prevent Alarm Storms
The Ekip self-test addresses electronics. It does not test the mechanical breaker itself, and on the ABB Emax 2 most repeated alarm conditions we have traced back to one of the following:
Contact wear and asymmetry
An ABB 1SDA070861R1 E1.2B 1600 running close to rated current will show contact wear after roughly 10,000 mechanical operations or 1,500 electrical operations at In, per the maintenance schedule in the ABB Emax 2 maintenance manual. Worn contacts increase resistance, raise local heating, and eventually trigger Tmax warnings on the Ekip. Measure contact resistance annually with a 100 A DC micro-ohmmeter; replace if values exceed the manual's threshold (typically 50 µΩ for E1.2 frames).
CT and Rogowski coil seating
The current sensors plug into the moving part of the breaker. After racking in/out 30+ times in a withdrawable execution, the connectors fatigue. A loose CT will produce phantom phase imbalance alarms or "sensor error" codes. Inspect connectors at every major outage.
Firmware management
ABB releases Ekip firmware updates roughly twice a year. Some updates fix known false-trip bugs (we have seen one specifically related to G-protection on harmonic-rich loads). Maintain a fleet firmware register; update during planned outages, never on a live critical bus.
Sizing and Selectivity Considerations That Reduce Alarm Frequency
Many of the alarm conditions listed above can be designed out before the breaker is even installed. The starting point is correct frame and rating selection. The interactive method we use is documented in How to Size ABB Emax 2: Step-by-Step Calculator for LV Distribution Panels, but the principle is simple: choose a frame where the design load sits between 60% and 80% of In. Below 60%, you lose measurement resolution and you are over-paying. Above 80%, normal load excursions will trigger pre-alarms.
For motor-dominated feeders, also consider whether MasterPact MTZ would suit the application better — a structured comparison is given in ABB Emax 2 vs Schneider MasterPact MTZ. Both platforms have strengths; the diagnostic ecosystem is one of the differentiators.
Selectivity with downstream MCCBs and MCBs is the other prevention lever. Stoklink stocks the full range of air circuit breakers, miniature circuit breakers, residual current devices and protection relays needed to build a properly graded protection scheme.
A coordinated study using ABB DOC software, with all settings documented and saved into the Ekip via Ekip Connect, is what separates a trouble-free installation from one that generates an alarm every other week.
The case for LSI vs LI trip units
If your installation has any meaningful downstream selectivity requirement — and almost every industrial main-distribution board does — specify an LSI variant such as the ABB 1SDA070782R1 E1.2B 1000 Ekip Dip LSI rather than the LI version.
The S (short-time delay) function is what allows the upstream Emax 2 to wait while the downstream Tmax XT clears a fault. Without it, both breakers race to trip and you lose the entire bus on a single feeder fault. We see this mistake on roughly one in four retrofit projects.
HR (high reliability) versions for critical buses
The "HR" suffix on units like the ABB 1SDA070981R1 E2.2B 1600 Ekip Dip LI HR indicates high-reliability rear terminations rated for elevated continuous current. On data centre and hospital incomers, this matters: a heat-stressed termination is a future Tmax alarm waiting to happen.
Communication-Layer Diagnostics: Pulling Data From the Bus
On any switchboard with more than three ABB Emax 2 breakers, the diagnostic strategy should not depend on someone walking up to each unit. The Ekip Com modules — Modbus RTU/TCP, Profibus DP, Profinet, EtherNet/IP, IEC 61850 — expose the entire alarm and measurement set to SCADA.
The IEC 61850 logical nodes most relevant for fault diagnosis are XCBR (circuit breaker), PTOC (time-overcurrent), PTRC (protection trip conditioning) and RREC (auto-reclose, where used). A SCADA point list mapped to these nodes gives you remote visibility of the same trip cause, phase, and current value that the local Ekip displays.
In one cement plant we audited, the maintenance team had been replacing "faulty" Ekip units for two years. Once we mapped the GOOSE messages to a historian, we found that 80% of trips were a single 11 kV upstream voltage dip propagating through a stiffly-set undervoltage protection on six Emax 2 incomers. No trip unit was faulty. The protection scheme was wrong.
Related Reading
- ABB Emax 2 Nuisance Tripping: Root Causes, Diagnostic Steps and Fixes
- How to Size ABB Emax 2: Step-by-Step Calculator for LV Distribution Panels
- ABB Emax 2 Full Technical Specifications: Current Ratings, Breaking Capacity and Dimensions
- ABB Emax 2 in Data Centers: MDB Design, Redundancy and Uptime Considerations
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Frequently Asked Questions
What is the difference between a warning and an alarm on an Ekip trip unit?
A warning (yellow indicator) is a pre-trip condition — the breaker is still closed but a measured value has crossed a configured threshold, for example 90% of I1 long-time pickup or an internal temperature above 75 °C. An alarm (red indicator) means the breaker has tripped or a self-diagnostic fault has been detected. Warnings are your opportunity to act before the lights go out; treat every warning as a work order.
How do I read the event log on an Ekip Dip without a TFT screen?
Plug the supplied USB or Bluetooth dongle into the front Ekip T&P test connector and open the free Ekip Connect software on a laptop or phone. The full event log, present settings, and live measurements are available even on the basic Ekip Dip variant. No screen on the breaker does not mean no data — it means the data lives in the chip until you ask for it.
Can I reset an Ekip alarm without ABB service intervention?
Protection trips (L, S, I, G, Iinst) are reset by pressing the iTest/reset button on the front of the trip unit, after the cause has been investigated and cleared. Self-diagnostic alarms — ROM/RAM error, trip coil fault, sensor error — generally cannot be cleared by reset and require trip-unit replacement. The unit will revert to a hardware-only protection mode in the meantime, which is safe but loses metering, communication and adjustability.
Why does my Emax 2 keep tripping on G (ground fault) when there is no actual earth leakage?
The most common cause is a downstream neutral-to-earth bond, which creates a parallel path that the Ekip's residual sum (Σi = IA+IB+IC+IN) detects as ground current. Other causes include high-frequency leakage from VFD common-mode currents, and incorrect polarity on the external neutral CT. Verify the bonding scheme against IEC 60364-4-41, then check the neutral CT polarity. The diagnostic flow is covered in detail in our nuisance-tripping article linked under Related Reading.
Is the Ekip trip unit field-replaceable, and does it need recalibration?
Yes — the Ekip is designed as a field-replaceable module on all Emax 2 frames. ABB ships factory-calibrated units; no field calibration is required. After replacement, you must reload your protection settings (use Ekip Connect to export from the old unit and import to the new one), verify the rating plug matches the breaker frame, and run the iTest self-check. Allow about 30 minutes per breaker including documentation.
What standards govern Ekip trip unit performance and self-monitoring?
The primary standard is IEC 60947-2:2019, with Annex F specifically addressing electronic trip units (test conditions, accuracy classes, self-diagnostic requirements). For systems sold into North America, equivalent UL 1066 and ANSI C37.50 requirements apply. IEEE C37.90 covers surge withstand for the relay electronics. The communication layer for substation automation is governed by IEC 61850-7-4 logical nodes.
Conclusion
Diagnosing Ekip alarm codes is not magic — it is a disciplined process of pulling the event log, correlating with measurements, eliminating downstream causes, and verifying trip-unit health. The Emax 2 platform gives you more diagnostic information than any LV breaker generation that came before it, but only if you use the tools: Ekip Connect on every commissioning visit, communication mapping into SCADA, firmware management as part of planned maintenance, and contact-resistance checks at every major outage. The plants that do this see one or two real protection events per year. The plants that don't see one or two unexplained trips per month and slowly lose faith in their switchgear.
For the full selection methodology, application matrix and maintenance schedule across the Emax 2 range — from the 630 A E1.2B up to the 6300 A E6.2 — see the ABB SACE Emax 2 Air Circuit Breaker: Selection, Application and Maintenance Guide. And when you are ready to specify, the full inventory of ABB air circuit breakers at Stoklink covers every Ekip variant, frame size and termination configuration discussed in this article.
