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DGUV Information 209-093 · Highest Qualification Level – Series Vehicles

HV Training Level 3S
Live HV Work – Series Vehicles

€1,099
per person
excl. VAT

The HV Training Level 3S is the highest qualification level for series vehicles per DGUV Information 209-093. Graduates may perform measurements, fault-finding and diagnostics under active HV voltage – with appropriate PPE and proven measurement competence. Prerequisite: valid Level 2S qualification.

Get a Quote All Course Levels
24
teaching periods (45 min each) total
≥ 16
Units practical
3
Training days
€1,099
per person excl. VAT
Target Group

Who is Level 3S for?

Level 3S is exclusively for qualified professionals with a valid Level 2S qualification who regularly need to carry out complex HV diagnostics.

HV Specialists
Senior automotive mechatronics engineers in authorised workshops handling complex diagnostic cases
Service Centre Technicians
Technicians at OEM manufacturer service centres and regional competence hubs
OEM Quality Assurance
QA specialists in production who must inspect HV systems under active voltage
Fleet Operators
Senior HV technicians at large EV fleets with in-house workshop operations
Battery Specialists
Specialists in second-life applications or battery reconditioning and diagnostics
HV Trainers & Instructors
Persons who deliver HV training up to Level 2S and require top-level expertise
Curriculum

What does Level 3S cover?

Level 3S builds on Level 2S and extends competencies to include safe working under active HV voltage – with advanced measurement and diagnostic methodology.

⚡ Theory – approx. 8 TP

  • Advanced HV system engineering: HV topologies, switching behaviour, BMS protocols
  • Hazards when working under voltage: body current flow, arc flash energy
  • Extended PPE: arc flash protection class, Class 1 insulating gloves
  • Measurement and test equipment for live measurements (CAT III/IV, insulation testers)
  • Insulation resistance measurement and insulation fault location (IMD evaluation)
  • Fault diagnosis on traction battery, inverter, OBC, DC/DC converter
  • Diagnostic software and manufacturer tools for HV systems
  • Emergency measures, first aid and post-accident HV response
  • Risk assessment for live HV work per TRBS 2131
  • Documentation obligations and reporting

🛠 Practical – min. 16 TP

  • PPE donning and full inspection before live exercises
  • Insulation resistance measurement on active HV system
  • Multi-point voltage measurement under operating voltage (400–800 V)
  • Live fault diagnosis: simulate and locate insulation faults
  • Diagnostic tool use: OBD/HV system readout under voltage
  • Emergency drill: response sequence for HV accident/arc flash
  • Final assessment: oral learning objective check + practical demonstration
On-site only: The live practical exercises under active voltage cannot be conducted remotely. The entire course takes place as an on-site inhouse training.
Level 2S is a mandatory prerequisite

Level 3S is an advanced course. Fully completed Level 2S is a mandatory prerequisite under DGUV 209-093 (Section 5.1.5). Enrolment without a valid Level 2S certificate is not possible.

Prerequisites

Who can attend Level 3S?

Level 3S is an advanced qualification – entry without Level 2S is not possible.

Entry requirements

  • Valid Level 2S qualification (participant certificate required)
  • Demonstrable professional experience with series vehicles after obtaining Level 2S
  • Valid employer instruction (recommended)
  • Physical fitness for wearing extended PPE
Series vehicles only: Level 3S applies to vehicles after SoP with standardised safety concepts. For prototypes and development vehicles, Level 3E is required.

After training you may:

  • Perform measurements and diagnostics under active HV voltage independently
  • Measure insulation resistance and locate insulation faults
  • Diagnose HV components in operating condition
  • Act as the most senior HV expert in the company
  • Take over complex fault diagnoses for other Level 2S FHVs
  • Prepare and authorise risk assessments for live work
Duration & Schedule

How is the Level 3S training structured?

24 teaching periods (45 min each) spread over 3 training days – at least 16 TP of which are practical work under active voltage – exclusively as on-site inhouse training.

DAY 1 · THEORY

System Knowledge, Hazards & Diagnostics

  • Revision and deepening of Level 2S
  • Advanced HV system topologies
  • Hazards under active voltage (arc flash, body current flow)
  • PPE for live work – selection and inspection
  • Measurement equipment CAT III/IV, IMD evaluation
  • Risk assessment for live work, emergency measures
DAY 2 · PRACTICAL I

Live Measurements on the HV System

  • PPE donning – mutual full inspection
  • Insulation resistance measurement on active HV system
  • Voltage and current measurement under operation (400–800 V)
  • OBD and manufacturer diagnostic software in practice
DAY 3 · PRACTICAL II + ASSESSMENT

Fault Diagnosis & Conclusion

  • Fault diagnosis: simulate and locate insulation faults
  • Emergency drill (simulated HV accident)
  • Final assessment: oral learning objective check + practical demonstration
  • Certificate issuance
On-site nationwide: We come to you. You need a suitable training room and a series vehicle with an active HV system for the practical day. PPE and measuring equipment are provided.
Proof of Qualification

Participant Certificate for Level 3S

After passing the learning objective check and practical demonstration, all participants receive a personalised certificate per DGUV Information 209-093.

The certificate documents:

👤
Name and qualification level (Fachkundige Person Hochvolt (FHV) 3S – Series Vehicles)
📋
Training content per DGUV Information 209-093, Level 3S
⏱
Training duration (24 TP, including ≥16 TP practical under voltage)
🗓
Training date and validity period (3 years recommended)
✍️
Signature of qualified trainer
🏢
Training provider: Hochvolt-Experten

The participant certificate is a proof of qualification per DGUV Information 209-093. The formal appointment as Fachkundige Person Hochvolt (FHV) Level 3S within the company is the employer's responsibility as part of the risk assessment process.

When does the qualification need refreshing?

DGUV clarifies in its official FAQ: a new course is not automatically required – but the qualification must be kept current. According to DGUV FAQ (Ch. 4.26), a refresh is required when:

  • New vehicle types or HV technologies are introduced (e.g. solid-state batteries)
  • Relevant standards or regulations are updated
  • New HV components or tools are introduced at your facility
  • More than 12 months have passed without active HV work

Regardless, the annual instruction under DGUV Regulation 1 remains mandatory. Annual instruction →

Frequently Asked Questions

FAQ – HV Training Level 3S

Is Level 2S strictly required before Level 3S?
Yes – Level 2S is the mandatory prerequisite. Level 3S builds on the competencies of Level 2S and requires safe mastery of de-energisation, PPE and voltage absence verification. Participation without a valid Level 2S qualification is not possible.
How long does the Level 3S training take?
24 teaching periods (45 min each) spread over 3 days. Day 1 covers the theory; Days 2 and 3 are devoted to live exercises under active HV voltage (at least 16 TP) and the final assessment.
What is the difference between Level 3S and Level 3E?
Level 3S applies to series vehicles after SoP with fully standardised safety systems (IMD, IPBS, defined HV shutdown paths). Level 3E is for prototypes and development vehicles where these standards cannot be assumed and greater individual responsibility is required.
What PPE is required for the Level 3S practical exercises?
Class 1 insulating gloves (up to 7,500 V), arc flash protective clothing per EN ISO 11612 (min. 8 cal/cm²), face shield with arc flash protection, and VDE-certified measuring instruments CAT III/IV. We supply all PPE and measuring equipment for the training.
How often must the Level 3S qualification be renewed?
Every 3 years and after more than 12 months without active HV contact, per DGUV Information 209-093. Many employers' liability insurance associations also require an annual instruction refresher.

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Enquiry & Booking

Level 3S Training for Your Team

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Keep your qualification valid

Don't forget the Annual Update Training

After completing your qualification, HV clearance must be refreshed annually per DGUV 209-093 – only then does your authorisation remain permanently valid.

Annual Update Training →