DEHNguard ACI
So that your system runs reliably
So that your system runs reliably
In the DEHNguard ACI, the switch/spark gap combination is connected in series with a varistor. At the end of the ACI surge arrester's life, any fault current that might flow through the varistor is interrupted. The series-connected switch/spark gap combination makes sure of this. The residual current is reduced to such an extent that not even the smallest system fuses trip. This means significantly higher availability and operational safety of the system compared to protection concepts using conventional Type 2 arresters with external backup fuses.
![](/sites/default/files/styles/3_2_ratio_1000_x_665/public/media/images/2024-05/DEHNGuard_MP_ACI_3_%2C20785.jpg?itok=edhcJDFj)
All benefits at a glance
Reliable dimensioning: Eliminate errors
With ACI arresters, you avoid possible design errors made when selecting or dimensioning a backup fuse. This increases system availability. The switch/spark gap combination is directly integrated into the arrester and ideally matched to it. For you, this means no more effort wasted on selecting the right fuse value and selectivity.
Conductor cross-section of only 6 mm²: Easier to install
A conductor cross-section of only 6 mm² Cu is always sufficient. You save valuable time previously spent dimensioning the cross-section. Just 6 mm² Cu also means easier installation due to smaller radii and thus shorter wiring. All active conductors should be wired so that they are short-circuit and earth-fault-proof.
TOV withstand: Increase system availability
Temporary overvoltage (e.g. due to neutral conductor interruptions) can destroy conventional surge protective devices. ACI arresters feature significantly improved TOV withstand. This increases the availability of your system. No damage means that you save time and money.
Zero leakage current: Increase arrester service life
With an ACI arrester, no leakage currents occur for technical reasons. This prevents premature ageing and thus the cost and time associated with premature replacement.
In addition, ACI arresters prevent the insulation monitoring from tripping, which contributes to operational safety.
Transition in the energy sector: Fulfil future requirements
The global power supply is changing. Renewable energy generation is creating new grid parameters. Island networks or storage systems influence the short-circuit conditions. With ACI technology, you are well equipped for these future requirements.
DEHNguard ACI product details
- Nominal voltage AC (UN): 230/400 V
- Max. continuous operating voltage (UC): 275 V
- Nominal discharge current (In) 20 kA
- Short-circuit withstand capability AC (ISCCR): 25 kA
- Additional external backup fuse
- Voltage protection level (Up): < 1.5 kV
- TOV withstand: at least 440 V
- Circuit configuration: 3+1, 4+0, 3+0, 2+0, 1+1
- Temperature range: -40°C to +80°C
The "no-worries solution" from DEHN
ACI technology: For maximum safety in the switchgear cabinet
No more time-consuming dimensioning! Our Type 1 and Type 2 arresters with ACI technology have an integrated switch/spark gap combination. This replaces the otherwise necessary backup fuse. This provides safety, enables flexible installation and raises system availability to a new level.
![](/sites/default/files/media/images/2024-02/DEH102303_Funkenstrecke_1300x1300px.gif)
The DEHN ACI technology
- Peak-level reliability and system availability
- Reliable dimensioning and space savings due to the elimination of the separate backup fuse
- Long service life thanks to high TOV withstand and zero leakage current
- Easy installation due to a smaller cross-sectional area
Product versions
![](https://www.dehn-international.com/thumbor/unsafe/fit-in/640x360/filters:fill(ffffff,false)/www.dehn-international.com/store/f/47832460/HDVORSCHAU/952341.jpg)
952341
DEHNguard M TT ACI ... FM
Modular surge arrester with Advanced Circuit Interruption (ACI) for TT and TN-S systems (3+1 circuit).
![](https://www.dehn-international.com/thumbor/unsafe/fit-in/640x360/filters:fill(ffffff,false)/www.dehn-international.com/store/f/47832444/HDVORSCHAU/952440.jpg)
952440
DEHNguard M TNS ACI ... FM
Modular surge arrester with Advanced Circuit Interruption (ACI) for TN-S systems.
![](https://www.dehn-international.com/thumbor/unsafe/fit-in/640x360/filters:fill(ffffff,false)/www.dehn-international.com/store/f/47832428/HDVORSCHAU/952330.jpg)
952330
DEHNguard M TNC ACI 275 FM
Modular surge arrester with Advanced Circuit Interruption (ACI) for TN-C systems.
![](https://www.dehn-international.com/thumbor/unsafe/fit-in/640x360/filters:fill(ffffff,false)/www.dehn-international.com/store/f/47832505/HDVORSCHAU/952121.jpg)
952121
DEHNguard M TT 2P ... FM
Modular surge arrester with Advanced Circuit Interruption (ACI) for single-phase 230 V TT and TN systems (1+1 circuit).
![](https://www.dehn-international.com/thumbor/unsafe/fit-in/640x360/filters:fill(ffffff,false)/www.dehn-international.com/store/f/47832489/HDVORSCHAU/952220.jpg)
952220
DEHNguard M TN ACI ... FM
Modular surge arrester with Advanced Circuit Interruption (ACI) for single-phase 230 V TN systems.
![](https://www.dehn-international.com/thumbor/unsafe/fit-in/640x360/filters:fill(ffffff,false)/www.dehn-international.com/store/f/47832533/HDVORSCHAU/952100.jpg)
952100
DEHNguard S ACI ... FM
Single-pole, separable surge arrester with Advanced Circuit Interruption (ACI) consisting of base part and plug-in protection module.
![](https://www.dehn-international.com/thumbor/unsafe/fit-in/640x360/filters:fill(ffffff,false)/www.dehn-international.com/store/f/47832472/HDVORSCHAU/952342.jpg)
952342
DEHNguard M TT ACI ... FM
Multipole surge arrester DEHNguard M ACI, type 2 according to EN 61643-11 with integrated ACI switch/spark gap combination.
![](https://www.dehn-international.com/thumbor/unsafe/fit-in/640x360/filters:fill(ffffff,false)/www.dehn-international.com/store/f/47832517/HDVORSCHAU/952122.jpg)
952122
DEHNguard M TT ACI ... FM
Multipole surge arrester DEHNguard M ACI, type 2 according to EN 61643-11 with integrated ACI switch/spark gap combination.
![](https://www.dehn-international.com/thumbor/unsafe/fit-in/640x360/filters:fill(ffffff,false)/www.dehn-international.com/store/f/47832355/HDVORSCHAU/942342.jpg)
942342
DEHNguard MP TT ACI ... FM
Multipole surge arrester DEHNguard MP ACI, type 2 according to EN 61643-11 with integrated ACI switch/spark gaps - combination for TT and TNS systems.
![](https://www.dehn-international.com/thumbor/unsafe/fit-in/640x360/filters:fill(ffffff,false)/www.dehn-international.com/store/f/47832411/HDVORSCHAU/942122.jpg)
942122
DEHNguard MP TT ACI ... FM
Multipole surge arrester DEHNguard MP ACI, type 2 according to EN 61643-11 with integrated ACI switch/spark gap combination.
Downloads
Brochures | ACI technology | Safety at the highest level! | .pdf 450 KB |
Brochure | CI- and ACI arresters | More safety in the switchgear cabinet | .pdf 1.27 MB |
White Paper | ACI | an innovative device concept for SPDs | .pdf 2.2 MB |
Have you got any questions?
Contact us!
Phone: 866-806-3098