How much can I load my cable reel?

with coiled cable

with a completely unwound line

AC cable reel

230V ~ 50Hz 16A

1100 Watt

3500 Watt

Three-phase cable reel

400V ~ 50Hz 16A

3000 Watt

9500 Watt

Three-phase cable reel

400V ~ 50Hz 32A

6100 Watt

19500 Watt

What types of cables do we offer?

  • H05VV-F: PVC cable, approved for use in dry environments.

  • H05RR-F: Rubber cable made of natural rubber. Approved for short-term outdoor use.

  • H07RN-F: Neoprene rubber cable, oil and UV-resistant, approved for permanent use outdoors and on construction sites.

  • AT-N07V3V3-F: The HEDI armored cable for particularly rough operation. Completely weatherproof, oil and acid resistant, microbe-proof and non-brittle. Robust against abrasion and crushing. Approved temperature range -35 ° C to + 80 ° C. Approved for permanent outdoor use. Attention! This type of cable is regulated by standards from Austria and is therefore not approved for commercial use in Germany!

  • H07BQ-F: The HEDI armored cable PLUS is the polyurethane manual for the highest requirements. Completely weatherproof, oil and acid resistant, microbe-proof and non-brittle. High mechanical strength and an approved temperature range of -40 ° C to + 90 ° C. Approved outdoors and on construction sites.

Why does the thermal circuit breaker trip?

  • The thermal circuit breaker is a protective device that must interrupt the circuit in the event of overheating so that there is no danger of excessive heating.
  • The temperature limit values ​​are prescribed by standards.
  • When rolled up, the cable drum heats up faster, even if only a few meters are still rolled up on the drum (please note the information on the type plate).
  • If machines with high power consumption are used without starting current limitation, the thermal protection switch must switch off when the permissible limit values ​​are exceeded.
  • When the drum is heated, two factors work together. On the one hand, it is the temperature of the reel itself that heats up through use, and on the other hand, it is the ambient temperature. These two temperatures add up.

Example: The thermal circuit breaker trips more quickly in cable reel operation at high ambient temperatures, even if the maximum load limit has not yet been reached. On the other hand, if the ambient temperature is low, it will only trigger later, even under high loads.


Bridging the thermal circuit breaker can lead to serious defects in the cable reel and to fire. In the case of changes of this kind, any liability on the part of the manufacturer expires and the person responsible is responsible for any resulting damage.


If the cable reel overheats, unroll it completely and let it cool down. Then press the red thermal circuit breaker button in the socket insert deeply.


The triggering of the thermal protection switch and thus the shutdown of the cable reel is a mandatory function and serves the user's own safety. When the ambient temperature is high or when large machines are used without the starting current limitation, the tripping of the thermal protection switch is mandatory and normal. This is not a defect!

Which cable type and cross-section do you need?

What material is the cable reel made of?

Plastic or sheet steel - that depends on the intended use. The trade association (DGUV-I 203-006) stipulates that only plastic cable reels may be used on German construction sites.

HEDI recommends a (all) plastic cable reel, as it is light and made of impact-resistant plastic. The advantage of using the plastic reel indoors is that sensitive floors can be protected from scratches.

The cross-section of the cable e.g. 25m H07RN-F 3G1.5 describes the cross-sectional area of ​​the conductor. And the area is responsible for the relevant electrical properties of the conductor. The required cross-section of the cable depends on a number of factors: The maximum current carrying capacity of the conductor, the length of the cable and the maximum permissible voltage drop.

Conductors with a high cross-section may be loaded with higher currents than conductors with a smaller cross-section.

Protective conductor resistance too high

in DGUV regulation 3 (formerly BGV A3) tests

A resistance limit value for protective conductors of 0.3 Ω is usually preset in test devices. This is also correct, at least for most devices that are subject to testing, which then have short connecting cables up to a maximum of 5 meters.

In the case of extension cables or cable drums, the cable is often longer. Therefore, the resistance limit value must be adjusted accordingly as described in the DIN VDE 0701-702 standard under point 5.3.

DIN VDE 0701-702 point 5.3

For cables up to 5 m in length and up to a rated current of 16 A, proof must be provided that the resistance of the protective conductor does not exceed the limit value 0.3 Ω. For longer cables up to a rated current of 16 A, the limit value may be increased by 0.1 Ω for every 7.5 m additional length up to a maximum value of 1 Ω.

An example with a 50 meter cable reel:

The first 5 meters ≙ 0,3 Ω

the remaining 45 meters divided by 7.5 = 6 (≙ 0.6 Ω)

Thus, for a cable drum with 50 meters of cable, a limit value of 0.9 Ω instead of 0.3 Ω applies

DGUV Information 203-006

(so far BGI / GUV-I 608)

DGUV-I 204-006 regulates the selection and operation of electrical systems and equipment on construction and assembly sites.

  • Only cables, cable reels and socket distributors with splash-proof sockets (protection class IP44 or higher) are permitted.
  • Use of H07RN-F and H07BQ-F cables.
  • In the case of cable reels, both the handle, the twist grip and the drum body must be made of an insulating material or be encased in one.

For more information, please refer to the current version of DGUV-I 203-006, which you can download on the Internet from the employer's liability insurance association.

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