Martindale is a specialist manufacturer of high-voltage busbar enclosures distributed at Thorne & Derrick. Delivering expert technical support, competitive pricing, and fast worldwide delivery. The BusBar Box is manufactured to meet Zone 1 & 21 hazardous area requirements and is fully type-tested, carrying ATEX and IECEx certification.
Drummond Clamps | G Clamps for Busbar Connections
drummond g clamps
G Clamps for Busbar Connections
The Drummond G-Clamp from Martindale Electric provides a safe, reliable and easy-to-use solution for tapping into bus bars without drilling. Suitable for CAT IV 600 V applications, these lightweight insulated clamps and kits are ideal for power monitoring, measurement and test equipment connections.The Drummond G Clamp makes connecting to bus bars straight forward.
- Fused at point of contact
- No need for tools
- Spring loaded contact pin and locking ring
- 4mm socket termination
- Colour coded for phase identification
- Drummond clamps are available in kit format
Thorne & Derrick distribute Substation Earthing Equipment for medium and high voltage electrical systems, typically distributing 6.6kV-11kV-33kV power – we provide competitive prices for MV-HV Substation Earthing Clamps & Cables, including operating poles, from extensive stocks to UK and international destinations.
G Clamps for Busbar Connections
Drummond G-Clamps are clamp-on connectors that attach securely to rigid rectangular bus bars using a spring-loaded contact pin and locking ring, eliminating the need for drilling. Colour-coded options simplify phase identification, and versions with built-in fuses offer added protection at the point of connection. These clamps are ideal for portable measurement and test equipment, temporary diagnostics, or any application requiring safe bus bar insertion via a standard 4 mm socket.
The fluted grip features of the G Clamp enable the clamping screw and locking ring nut to be tightened by hand while wearing appropriate PPE gloves, eliminating the need to use tools in the bus bar chamber.
Ideal for connecting power monitoring and measuring equipment, the new colour coded clamps make phase identification easy. The insulated materials reduce the hazard to the operator and the spring loaded contact pin and locking ring ensure reliable results throughout extended logging periods or for permanent monitoring.
The clamp-on design eliminates the need to drill bus bars and makes for a much safer, more reliable connection via a standard 4 mm socket. A 4mm shrouded socket is provided in the fluted head of the moulded screw. The connection is suitable for up to 10A continuous use at 600V AC, subject to appropriate rating of the 4mm plug and lead.
Drummond G-Clamps – Available Colours
Drummond G-Clamps are available in fused and unfused versions, with colour coding to simplify phase and neutral identification.
Colours vary depending on clamp type.
Black
Fused & Unfused
Brown
Fused & Unfused
Grey
Fused & Unfused
Blue
Unfused (Neutral)
Red
Unfused
White
Unfused
Note: Fused G-Clamps are supplied with a recessed 0.5 A HBC fuse as standard.
Alternative fuse ratings and custom lead assemblies are available on request.
Available individually and in 3 phase connection kit sets including a blue unfused G clamp for the neutral connection. The smaller barrel of the unfused design requires 25mm less clearance in front of the bus bar.
Individual G Clamps
DRUGCLAMP-F0.5-BK (Fused 0.5A Black)
DRUGCLAMP-F0.5-BR (Fused 0.5A Brown)
DRUGCLAMP-F0.5-GY (Fused 0.5A Grey)
DRUGCLAMP-BL (Unfused Blue)
drummond g clamp connection kit 1
Drummond GCK/F/KIT1 Set of four G Clamps, black, brown, grey fused and blue unfused.
- 3-phase connection kit: black / brown / grey fused and blue unfused
- Easy reliable connection
- No need for tools
- Spring loaded contact pin and locking ring
- 4mm socket termination
- Colour coded for phase identification
drummond g clamp connection kit 2
Drummond GCK/F/KIT2 Set of four G clamps black, brown, grey fused and blue unfused with 4m heavy duty colour coded CATIV test leads. The leads are terminated with 45 degree 4mm safety plugs at both ends.
- 3-phase connection kit: black / brown / grey fused, blue unfused & heavy duty leads
- Easy reliable connection
- No need for tools
- Spring loaded contact pin and locking ring
- 4mm socket termination
- Colour coded for phase identification
drummond g clamp connection kit 3
- 3-phase unfused connection kit: black / brown / grey / blue
- Easy reliable connection
- No need for tools
- Spring loaded contact pin and locking ring
- 4mm socket termination
- Colour coded for phase identification
drummond CAT IV Heavy duty leads set
- 4m heavy duty CAT IV test leads
- Terminated with 45 degree 4mm safety plugs at both ends
- Colour coded for easy phase identification
Drummond Clamps
Fused & Unfused G Clamps Technical Specification
| Function | Fused G Clamps | Unfused G Clamps |
| ELECTRICAL | ||
| Applied electrical contact force | 40N +/- 5N | |
| Maximum working voltage | 600V AC | |
| Maximum working current | 10A | |
| GENERAL | ||
| Dimensions | ||
| Length behind bus bar | 12mm | |
| Length in front of bus bar | 87mm | 61mm |
| (+ 35mm as minimum allowance for 4mm plug) | ||
| Height above top of bus bar | 14mm | |
| Width | 50mm for locking ring nut | |
| Clearance in front of bus bar | Required to withdraw fuse holder 75mm | |
| Materials | Nylon 66, reinforced with glass fibre | |
| ENVIRONMENTAL | ||
| Temperature (Operating & Storage) | -15°C to 60°C ≤ 80% R.H. | |
| Altitude | up to 2000m | |
| Pollution degree | 2 | |
| IP rating | IP40 (with connector in mated position). | |
| SAFETY | ||
| Conforms to | BS EN 61010-031:2015, CAT IV 600V | |
| Fuse | 6.35 x 32mm 600V 0.5A HBC For enhanced safety, the fuse is fully recessed inside the fuse holder until the fuse holder is withdrawn. |
N/A |
Drummond Clamps G Clamps for Busbar Connections – DatasheetDownload
