small box wallbox

Quad power - one eighth power loss: Panasonic Industry releases 40A printed HE-R relay for 3 phase systems with feedback contact. A perfect - and proven - match for EV charging wall boxes.

Let's start with a look back: Whenever it came to the task of handling high loads, application engineers suffered some headache in terms of relays. High power environments usually required the use of rather large, stand-alone contactors that had to be mounted as separate units with wired connections to a control board.
In the end, this resulted in higher component and material costs, additional manual assembly efforts and sometimes even the risk of poor operational reliability, because every single connection from the board to the cables and the socket to the relay connection can turn out to cause reliability issues.

HE: A new generation of PCB based power relays

To overcome these shortcomings and to serve the growing demands for safe, robust and energy-efficient ways to switch relatively large amounts of power on the PCB, Panasonic Industry introduced its HE relay series nearly 20 years ago, at this time with a focus on the solar energy plants market.

The lineup grew over the years, and now in 2022 HE relays can handle loads up to 120A (HE-N) and up to 1000VDC

(HE-V) in ambient temperatures of up to 85°C. This makes the PCB relay series a perfect choice for high power applications, such as solar inverters, automotive charging stations, or battery storage systems – while coming in remarkably compact dimensions. HE-S, for instance is as compact as 30x36x40mm.

HE Relay Series Panasonic Industry
Image 1: Panasonic Industry’s HE relays series specs at one glance – including the latest HE-R type.

HE-R: The small box for the wall box

Now, Panasonic Industry presented an interesting new member for the HE relays family: The new HE-R is the world's first PCB relay that can be used as the main switching element in three-phase systems.

Designed specifically for mode 3 AC charging stations up to 22kW, the HE-R is meant to take charging technology safety to the next level: Each of the four normally open contacts is designed for carrying and switching 40A within the series’ usual temperature range of up to +85°C. An optional NC contact, designed as a mirror contact according to IEC 60947-4-1, switches signal loads up to 10mA / 5VDC.

HE-R Relay  Panasonic Industry
Image 2: Compact housing, IEC 62955-certified – and outstanding features: New 40A HE-R from Panasonic Industry.

In addition to the HE-R’s small size of 35 x 58 x 47mm, its minimal power consumption would be a key feature. This could be achieved by using a pulse width modulation to reduce the coil voltage to only 35% of the nominal voltage. This results in a remarkably low power dissipation of only 490mW .  Positive side effect: A lower waste heat renders ventilation redundant in most of the cases.

HE Relay Series Panasonic Industry Load Performance Overview
Image 3: HE series DC load performance overview.

Size, performance, and robustness

The IEC62955 VDE-certified HE-R relay now allows to implement three-phase systems with just one relay directly on the PCB. This is not only an option for demanding garage and carport wall box designs, but also for public charging stations and completely different application areas such as industrial automation or energy harvesting.


HE-R features overview

  • Unique contact arrangement of 4a or 4a1b
  • 1xNC contact as a mirror contact
  • Contact rating 40A / 480VAC resistive
  • Extreme low coil holding power of 490mW
  • Clearance & creepage distance >8.0 mm
  • Ambient temperature - 40°C to +85°C
  • PCB soldering terminal type
  • UL/C-UL, VDE certified


Learn more on Panasonic Industry's current portfolio of HE relays:

HE relay

HE relay: TV-10/TV-15 rated; 1 Form A 30A and 2 Form A 25A

HE-R power relay Panasonic Industry

HE-R 40A power relay