Why Does My RCD Keep Tripping? Causes and Fixes
A diagnostic walkthrough of RCD nuisance tripping: cumulative leakage current, RCD type mismatches, moisture faults, and when to replace the device instead of chasing a repair.
10 min read
Technical
Technical for buyers and panel builders
Guides and notes on industrial electrical and automation parts: selection, wiring, settings and ordering.
- Articles
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MCCB Won't Reset After Trip: Troubleshooting
Why an MCCB won't reset after tripping, the correct OFF-reset-ON procedure, four root causes, and when to replace rather than reset.
10 min read
Monitoring Relays in Water and Wastewater Treatment
How level, phase-sequence, thermistor and insulation monitoring relays protect pumps and panels across water and wastewater treatment plants.
9 min read
VFD for CNC and Machine Tools
How VFDs drive CNC spindle motors: the constant-torque to constant-power transition, overload margins for interrupted cuts, and cabling and brand choices for retrofits.
8 min read
Overload Relays for Conveyor Motors
How to set overload relay trip class, FLC dial, and reset mode for conveyor motors, including star-delta sizing and multi-drive belt systems.
9 min read
Soft Starter SCR and Thyristor Failure Diagnosis
How to tell an open SCR from a shorted one in a soft starter, diagnose it with a multimeter or built-in protection, and find the root cause before replacing the...
9 min read
MPCBs in Motor Control Centers (MCC)
How MPCBs function as the branch-circuit protective device inside MCC combination-starter buckets, from bucket architecture and sizing to coordination and group protection.
10 min read
MCBs in Consumer Units and Final Circuits
How MCB rated current and tripping curve are selected per final circuit type in a consumer unit, with RCD/RCBO pairing and board layout guidance for panel builders.
10 min read
RCDs for Medical and Hospital Locations
A practical breakdown of medical location groups 0/1/2 under IEC 60364-7-710, why operating theatres run on IT systems instead of RCDs, and where 30 mA RCDs remain mandatory across the...
9 min read
Why Does My MCCB Keep Tripping? Causes and Fixes
A troubleshooting guide to diagnosing why an MCCB keeps tripping, separating overload, short-circuit, earth fault, and nuisance-trip causes.
10 min read
Monitoring Relays for Generators and ATS Systems
How phase-sequence, voltage/frequency and temperature monitoring relays let an ATS safely transfer a load onto a standby generator and back.
10 min read
VFD for Cranes and Hoists: Regenerative Braking
How to size VFDs for crane and hoist duty: four-quadrant loading, vector control, dynamic and regenerative braking, heavy-duty overload, and STO/brake coordination.
8 min read
Overload Relays for Fan and HVAC Motors
How to size and set thermal or electronic overload relays for fan and HVAC motors, covering run-up time, trip class, star-delta FLC setting, phase-loss protection, and reset mode.
8 min read
Why Does My Soft Starter Fault? Causes and Fixes
A troubleshooting guide to the most common soft starter fault codes — overcurrent, phase loss, shorted SCRs, undercurrent, and duty-cycle lockouts — with root causes and practical fixes.
8 min read
MPCB for Compressor Motors
How to size the thermal dial, choose the right trip class, and combine an MPCB with a contactor for reciprocating, screw, and scroll compressor motors.
9 min read
Best MCB Brands for Electrical Panels Ranked
Schneider Acti9, ABB S200/S800, and Siemens 5SY are ranked on curve range, breaking-capacity tiers, RCBO ecosystem, DIN accessory availability, price, and lead time for electrical panel builds.
10 min read
RCDs for Data Centers and IT Equipment: High Leakage
Why cumulative leakage from server PSUs, UPS rectifiers and VFD-fed cooling forces different RCD sizing, type and earthing choices in data centers than in a standard distribution board.
9 min read
MCCB for Capacitor Bank Protection
How to size an MCCB for capacitor bank protection, covering switching inrush, the 1.35-1.5x sizing multiplier, magnetic trip settings, harmonic derating, and contactor coordination.
9 min read
Monitoring Relays in HVAC and Building Services
Phase, current, temperature and level monitoring relays protect chillers, AHU fans, pumps, and cooling towers across HVAC and building services plant rooms.
9 min read
VFD for Compressors: Selection Guide
How to select and size a VFD for screw, reciprocating and centrifugal compressors, covering overload rating, turndown limits and energy savings.
9 min read
Overload Relays for Pump Motors: Selection and Setting
How to pick the trip class, set the dial, and choose a reset mode for pump motor overload relays across centrifugal, positive-displacement, and submersible applications.
10 min read
Soft Starter in HVAC Systems
How soft starters are applied on AHU fans, cooling tower fans, and chilled/condenser water pumps in HVAC plants, with sizing, ramp-down, and protection guidance.
9 min read
MPCB for Conveyor Motors
How to size the thermal dial, choose the right trip class for belt inertia, and protect conveyor motors with an MPCB.
10 min read
ABB S200 vs S800: Standard vs High-Performance MCB
ABB S200 and S800 MCBs compared on current rating, breaking capacity, standards, and the point where a feeder outgrows S200 and needs S800.
7 min read
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