The short answer
On the Black Decker BMG microwave an electrical complaint is usually the circuit the oven is plugged into rather than the oven itself. The BMG list is one machine in several colours, so the checks below hold across the model list — and all of them stay outside the cabinet.
What you observe
- Sparking or a flickering blue glow inside the cavity — Arcing.
- The breaker or a protective device trips when the oven runs — A load fault or a shared circuit.
- A hot plug or a warm cord — Resistance at a connection, and the one symptom on this page that is about the outlet rather than the appliance.
- NEAR MISS — a loud hum with normal heating — Many ovens are simply loud under load.
Causes, most likely first on the BMG family
- The outlet, plug and what shares the circuit — First on this family — the BMG list is one machine in several colours — and an oven of this class is usually plugged into a general kitchen outlet rather than a dedicated one. An oven sharing a circuit with a kettle or a toaster trips it without anything being faulty at all.
- A worn outlet or an extension lead — Second, and the cause behind a hot plug: contacts that no longer grip heat under load. An extension lead makes it worse and should not be used for this appliance at all.
- Arcing inside the cavity — Third: it trips nothing as a rule but it is what people notice first, and it is free to check before anything electrical is suspected.
- Internal high-voltage components — Last: a genuine internal fault trips the breaker the instant the oven is asked to heat, repeatably, on a circuit with nothing else on it — and that is the point at which the oven goes to a technician or to the tip.
Check in this order, and why
- Run the oven alone on the circuit with nothing else drawing — First and free: if it stops tripping, the circuit was shared and no repair is needed.
- Feel the plug and the outlet after a few minutes — Second: warmth at the plug is a connection fault, and it is a fire risk regardless of what the oven is doing.
- Remove any extension lead entirely — Third — it is both a common cause and a condition that hides the real one.
- Watch for tripping at the exact moment heating begins — Last of the owner checks, and the pattern that points inside the cabinet rather than at the wall.
Before you open anything
Safety
Unplug the oven before touching anything beyond the cavity and the door — and then still do not open the cabinet: the high-voltage capacitor inside can hold a lethal charge long after the oven is disconnected, which makes this the one kitchen appliance that can injure you after it is switched off. Never tape, wedge or otherwise defeat a door interlock, never run the oven empty, and stop using it altogether if the door, its inner panel or its mesh is bent, cracked or burned.
Models in the BMG family
Reference| Model number | Family key |
|---|---|
| BMG07BL | black-decker:microwave:bmg |
| BMG07WL | black-decker:microwave:bmg |
When to call a technician
Call, or replace the oven, if it trips a breaker on a circuit with nothing else on it, if there is a burning smell with a clean cavity and clear vents, or if sparking repeats in the same place with nothing metallic in the load. Call an electrician rather than an appliance technician if the plug or outlet is hot — that fault is in the wall, not the oven.
Other faults covered for the BMG family
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
