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Delivering training services for the Built Environment and Utility sectors since 2004, we operate from our purpose-built training facilities and regional offices located in Southeast London, the East Midlands and West Yorkshire, with the use of over 100 training centres nationwide.

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Low Voltage Cable Identification (DNO)


It is critical to the safety of operators and engineers to identify cables correctly - before being worked on and to ensure they are being powered appropriately. Failure to label cables and wires or do so incorrectly can lead to electrocution and fire risk if they are damaged, cut or unplugged in error. With so much reliance on a massive infrastructure of cables and wires, it is crucial that workers have the knowledge and equipment to do their work safely on them and that they can make sure everything is powered correctly.

There are four approved cable ID methods, under DSR 010018. This Citrus Low Voltage Cable Identification (DNO) qualification takes delegates through the techniques, procedures and regulatory requirements of identifying low voltage cables using the specialist kit and approved methods.

Course Outline

This Citrus Low Voltage Cable Identification (DNO) qualification gives delegates the understanding, skill, knowledge, and competence to carry out low voltage identification on live cable networks through a mix of practical and theory-based exercises and tutorials.

The course reflects national standards and industry best practices and is fully accredited in line with regulations. In addition, choose to learn with Citrus, and delegates will benefit from our custom-built training facilities and customer-first approach.

Our occupationally and technically-experienced trainers coach delegates on this course in the Jointing School, completing the session with a practical observation and short answer question paper. They must pass the assessment to qualify for the Citrus certificate of attendance, valid for three years.    

Once delegates have the certificate of attendance, this then allows them to work under personal supervision until they complete their trade test or authorisation assessment.

Course Programme

Delegates taking this Low Voltage Cable Identification (DNO) qualification will cover knowledge, skills and operating practice using a Grumbler.

Course content includes:

  • Jointing practices and procedures 
  • Health and Safety regulations and legislation relating to electrical work  
  • Control of Substances Hazardous to Health (COSHH)  
  • Appropriate PPE for low voltage Jointing    
  • Understanding Network drawings 1/500 
  • How to use a grumbler (signal injection live line decoder) 
  • How to carry out risk assessments
On Completion

Upon successfully completing this qualification, delegates will be able to identify low-voltage cables under personal supervision. Once they complete ten cable identification tasks with a portfolio of evidence, they can take their on-site assessment and authorisation to sign off as fully competent in identifying low-voltage cables on the network.

Who Should Attend?

This Citrus Low Voltage Cable Identification qualification is for anyone needing to identify a low-voltage cable in their line of work.

Delegates must already be authorised to low voltage switches (linking and fusing) and have good knowledge, understanding, and experience working on the network. Roles include: 

  • Low Voltage Jointer
  • Lines man
  • Fitter
  • Authorised Person
Course Duration

This is a one-day comprehensive training programme for Low Voltage Cable Identification.

Why Citrus?

We dedicate our efforts to unrivalled quality and the customer experience at Citrus Training. As a result, we are the leading UK-based provider of health, safety and technical training and assessment services to the Built Environment and Utility sectors. 

Citrus Training serves 85 of the top 100 building services companies in the market. With over 20 years of collective experience, we offer advice and guidance for new and experienced entrants looking to work within the IDNO/DNO industry. 

Our Electrical training is accredited, regulated, and of an exceptionally high standard. Delivered by our Electrical Safety trainers and DNO Trained Assessors, they also carry out competency pre-assessment and testing to work on IDNOs and DNOs. 

Finally, we teach and promote current industry and legislative requirements to ensure delegates take them forward into their daily working lives, delivering courses at our nationwide, industry-leading and accredited training centres to offer the very best of training standards and quality assurance. 

Things You Need to Know

To take this course, delegates must already be authorised and competent for low voltage switching (link and fusing) and have experience in:

  • Substation entry  
  • Confined spaces  
  • First aid at work  
  • Manual handing

Before starting the course, they must inform their trainer of any special considerations, medication or physical restrictions that may cause difficulties in any part of the training.

PPE must be worn, which delegates will need to provide:

  • Flame retardant overalls  
  • Safety footwear  
  • General purpose gloves  
  • LV gloves  
  • Protective eyewear safety glasses  
  • full face visor  
  • Hard hat 
  • Hi-vis clothing

All delegates must bring a passport photograph to the training to produce ID cards. 

National Coverage

Over 100+ training centres nationwide, with 150+ technical trainers, delivering upwards of 250+ courses to over 40,000+ delegates each year. Thats why we're the UK's trusted training provider.

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