ID HQ SERIES COIL [9557NB] [4.5"] ANGLE GRINDER SPARE PART - 30127
Chat with us
Choose options
Restore Full Power — The Right Part, The Right Fit, The First Time
The ID HQ Series Coil [9557NB] is a precision-engineered angle grinder spare part designed as a direct replacement for the 4.5" HQ Series angle grinder. Built with high-grade copper wire windings, advanced insulation, and a robust magnetic core, this field coil efficiently converts electrical energy into mechanical energy to restore full power output to your tool. Engineered for high-temperature resistance and long-term durability, it is the trusted choice for professional tradespeople and workshop technicians who demand reliable power tool repair solutions.
| Key Features | Perfect For |
|---|---|
|
|
- Direct OEM Replacement — Part No. 30127: Engineered specifically for the ID HQ Series 9557NB 4.5" angle grinder, this coil matches original factory tolerances exactly, eliminating the guesswork of cross-compatibility and ensuring a precise, secure fit with no modification required.
- Premium Copper Wire Windings for Maximum Efficiency: The coil is wound with high-conductivity copper wire that minimises resistive losses, ensuring the maximum amount of electrical energy is converted into rotational mechanical force — delivering the full rated RPM your grinder was designed to achieve.
- High-Temperature Resistant Insulation System: Each winding layer is coated with thermally stable insulation rated for the elevated operating temperatures of sustained grinding, cutting, and surface-preparation work, preventing coil failure due to thermal breakdown — a common cause of motor burnout.
- Precision Magnetic Core for Optimal Electromagnetic Performance: The laminated silicon-steel magnetic core is precision-stamped to reduce eddy current losses, improving the electromagnetic efficiency of the coil assembly and maintaining consistent torque output even under variable load conditions.
- Genuine ID Brand Quality — Engineered for Longevity: This spare part is manufactured under the same quality standards as the original component, meaning the repaired tool will perform at its rated specifications. It is packaged as a standalone replacement coil, accompanied by the product warranty documentation, making it ready for immediate workshop installation.
General Purchase & Comparison Queries
Is this coil compatible with my ID HQ Series angle grinder?
This coil — Part No. 30127 — is specifically designed and manufactured as a direct OEM replacement for the ID HQ Series 9557NB 4.5" angle grinder. If your grinder carries the model designation 9557NB and uses a 4.5" disc, this is the correct replacement coil. We recommend verifying the part number on your existing coil or referring to your grinder's service manual before ordering.
Is this a genuine ID brand spare part or an aftermarket component?
This is a genuine ID brand spare part, manufactured to the same specifications as the original component that ships with the HQ Series 9557NB angle grinder. Genuine parts ensure dimensional accuracy, correct winding resistance, and insulation integrity — factors that directly affect tool performance and safety. Aftermarket coils may not meet these standards and can reduce motor efficiency or shorten tool lifespan.
How does replacing the coil compare to buying a new angle grinder?
Replacing the field coil is a highly cost-effective alternative to purchasing a new tool. A failed coil is one of the most common repairable faults in an angle grinder — the housing, gearbox, disc guard, and switch are typically undamaged. By installing a new ID HQ Series coil (Part No. 30127), you restore the grinder to its full rated performance at a fraction of the cost of a new unit, making it the smarter choice for professional workshops and budget-conscious tradespeople alike.
Product-Specific and Usage Queries
What does the coil do inside an angle grinder?
The field coil (also called the stator coil) is a core component of the angle grinder's electric motor. It consists of copper wire windings wound around a laminated magnetic core, which generates a rotating electromagnetic field when energised. This field interacts with the armature (rotor) to produce the rotational force that spins the grinding disc. Without a functioning coil, the motor cannot generate sufficient torque and the tool will either run poorly or fail to start entirely.
Can I install this coil myself, or does it require a professional technician?
Coil replacement on an angle grinder is a moderate-level repair task. It requires disassembling the motor housing, removing the old coil, fitting the new ID HQ Series coil (Part No. 30127), and reassembling the unit. While experienced DIYers or workshop technicians with basic electrical knowledge can perform this repair, we recommend the task be carried out by a qualified power tool service technician to ensure correct installation, safe reassembly, and to preserve any remaining tool warranty.
What are the signs that my angle grinder coil needs to be replaced?
Common indicators of a failing or failed field coil include: the grinder not starting despite the switch and power supply being functional; a significant loss of power or RPM under load; excessive heat emanating from the motor body during use; a burning smell during or after operation; or visible scorch marks and discolouration on the coil windings when the motor housing is opened. If you notice any of these symptoms, the coil should be tested and replaced promptly to prevent damage to other motor components such as the armature or brushes.
Problem/Solution-Oriented Queries
My angle grinder has lost power and runs slowly — can a new coil fix this?
A degraded or partially failed field coil is a common cause of reduced power and slow RPM in an angle grinder. When the copper windings develop short circuits between layers or the insulation breaks down, the coil can no longer generate a full-strength electromagnetic field, leading to a weaker motor output. Replacing the coil with a new ID HQ Series coil (Part No. 30127) restores the correct electromagnetic characteristics of the motor, bringing the grinder back to its full rated power and speed — provided the armature and brushes are also in serviceable condition.
My grinder smells like burning — is the coil the problem?
A burning smell from an angle grinder is a serious warning sign that typically indicates the motor's insulation is overheating or has already failed. The field coil's insulation is designed to withstand high operating temperatures, but prolonged overloading, blocked ventilation, or extended continuous use can cause it to break down. Stop using the tool immediately and inspect the coil visually for scorch marks or discolouration. If the coil insulation has failed, it must be replaced — continued operation risks a complete motor burnout or an electrical fault. The ID HQ Series coil (Part No. 30127) is the correct replacement for the 9557NB model.
Will fitting a new coil fix my grinder if it is completely dead and won't turn on?
A completely non-starting angle grinder can be caused by several faults, and a failed field coil is one possibility. Before replacing the coil, it is advisable to rule out other common causes such as a faulty power switch, worn-out carbon brushes, or a broken power cable — these are often simpler and less expensive to address first. If the switch, brushes, and cable test as functional and the coil shows an open circuit or significantly incorrect winding resistance when tested with a multimeter, then replacing the coil with Part No. 30127 should restore normal operation to your ID HQ Series 9557NB grinder.