Switchgear
The backbone of any low-voltage installation: circuit breakers, contactors, residual current protection and transfer switches, all held in stock.
Protection, switching and control
10sub-categories
Selecting switchgear means weighing breaking capacity, discrimination and available mounting space together. We review current ratings against your single-line diagram and present comparable alternatives with the right curve and breaking capacity wherever discrimination is required. Working with Schneider Electric, Siemens, Sigma Elektrik and Himel lets us offer several budget levels for the same function.
What this group covers
- Miniature circuit breakers
- Residual current devices
- Moulded case circuit breakers
- Load break switches
- Motor protection circuit breakers
- Contactors and thermal overload relays
- NH fuses and fuse bases
- Surge protection devices
- Impulse relays
- Transfer switches
How to choose the right product in this group
These are the same criteria we check when preparing a quotation. Send us your list and we run these checks on your behalf.
- 01
Breaking capacity (kA)
Chosen against the prospective short-circuit current at that point. Main distribution close to the transformer needs a high value; final circuits need less. Insufficient breaking capacity destroys the device itself during a fault.
- 02
Tripping curve (B, C, D)
Curve B suits lighting and socket circuits, C mixed loads, and D motors and transformers with high inrush. The wrong curve causes either nuisance tripping or late protection.
- 03
Discrimination
In a fault, only the affected feeder should open. This needs a current and time margin between upstream and downstream devices; for residual current protection a time-delayed (type S) device is used at the incomer.
- 04
RCD type (AC, A, B)
Electronic loads such as drives, power supplies and LED drivers produce residual currents with DC components. Such circuits need at least type A, and drive outputs need type B.
The mistakes we meet most often on site
- Choosing breaking capacity on price and fitting a low-kA device in main distribution.
- Using a B curve on a motor feeder and being surprised when it trips at every start.
- Fitting a type AC RCD on a line with drives — it may never trip in a real fault.
- Ordering contactors without checking coil voltage (mixing 24 V DC and 230 V AC).
- Selecting terminals and lugs that do not match the conductor size, causing hot joints.
Terms you will meet in quotations and specifications
The concepts that come up most often in correspondence about this group, with short definitions.
- Breaking capacity (Icu / Ics)
- The largest fault current the device can interrupt without damage. Icu is the ultimate value, Ics the service value at which it keeps working.
- Tripping curve (B / C / D)
- Shows at what multiple of rated current magnetic tripping occurs. B is low, C medium and D suits loads with high inrush.
- Discrimination (selectivity)
- Only the device closest to the fault opens while upstream devices stay closed, achieved through current and time margins.
- IΔn (residual current rating)
- The residual current at which the device trips. 30 mA is for personal protection, 300 mA for fire protection.
Frequently asked about Switchgear
Can you offer different brands for the same function?
Yes. Working with Schneider Electric, Siemens, Sigma Elektrik and Himel lets us offer equivalent products at different budget levels. Technical differences and lead times are stated per line in the quotation.
I have no single-line diagram — can you still make a selection?
We can. We start from a load list, motor nameplates or photographs of the existing panel. If needed we survey on site and produce the single-line diagram ourselves.
How do I choose between NH fuses and circuit breakers?
NH fuses clear high fault currents quickly and cost less, but must be replaced after operating. A breaker is reusable and adjustable; where measurement and remote monitoring are wanted in main distribution, a breaker is preferred.
Is using an equivalent risky in switchgear?
There is no risk as long as the technical values match (breaking capacity, curve, number of poles, rated current). Where the specification mandates a brand we follow it; otherwise we present equivalents in writing with their differences.
How many poles should the device have?
Use 1P+N for single-phase loads and 3P for three-phase. Where the neutral must also be broken (generator transfer, TT systems) 4P is preferred. On RCDs the neutral must always pass through the device.
Explore the other groups
- Industrial AutomationPLC, drives, servo, robotics
- Cable and ConnectionPower, control, terminals, termination
- Enclosures and PanelsSheet-steel enclosures, busbars, climate control
- Cable ManagementTrunking, conduit, spiral wrap
- Control and SignallingPushbuttons, boxes, crane pendants
- Tools and ConsumablesCrimping, cutting, marking
Have a project or a material list?
Send us your list; we return stock status, lead time and wholesale pricing the same day.