Charging Relay 140 A / 12 V

30 in stock
SVB price: €29.37
Excl. VAT, excl. shipping costs.
This is a NET-price excluding German VAT. Shipments to countries outside of the EU may be subject to import duties and taxes.
€29.37 This is a NET-price excluding German VAT. Shipments to countries outside of the EU may be subject to import duties and taxes.
Available variants:
Item no.
Charging relay 12 V / 140 A

Product details

This high-quality, water-sealed and voltage-controlled charging relay enables the simultaneous charging of two separate batteries. It is ideally suitable for connecting an existing on-board power system to an additional battery, without any complications occuring in the existing installation. It operates fully automatically - the integrated measurement technology detects the (charge) voltage at both terminals. When the alternator is running, or when the charging voltage is >13.3 volts, the charging relay connects both batteries and charges them simultaneously. A red LED indicates the operating state of the unit. As soon as the voltage of the batteries falls below 12.8 volts, the relay disconnects the batteries. Thus, with very little effort, it is possible to ensure that the batteries within the on-board network are not unintentionally discharged. Moreover, it also ensures that sensitive electronics which are connected to a consumer battery are protected against interfering signals and voltage spikes when starting the engine.

Battery speration can also occur if the alternator does not provide enough energy due to insufficient engine speed (idling) or if the second battery has a very low amount of charge. In both cases, increasing the RPM helps.

Installation is very easy! Select an installation location in the immediate vicinity of the starter battery. Attach the lower relay cover to the installation location using the two short screws. Make the necessary electrical connections. Place the relay on the lower cover and secure it on to the installation location with the two long metal screws. For the electrical connection of the POS cables, you need ring or fork cable lugs with a 6 mm bore / fork opening. The red-marked bolt is connected to the starter (main) battery. Connect the "thin" black NEG cable of the relay directly to the NEG battery connection. Look at the thread diameter of the NEG battery terminal block and use a ring or fork cable shoe with a suitable hole / fork opening. We recommend using high-load fuses in the POS lines and a 1 A fuse in the NEG line of the charging relay.

Technical specifications
  • Dimensions: L x W x H: 68 x 68 x 50 mm
  • Connections:
    • 2x threaded bolts M6 (including nuts and Z-washers)
    • 1x negative connection cable with black silicone insulation, approx. 45 cm long
  • Operating display: red control LED on the frontside of the housing
  • System voltage: 12 V DC
  • Switch-on voltage for each type: >13.3 V
  • DC Switch-off voltage for each type: <12.8 V DC
  • Load capacity: 140 A
  • Idle current consumption: approx. 10 mA
  • Operating current consumption: approx. 250 mA
This charging relay is designed for use in wiring systems with lead-acid battery types (also AGM and gel).

It monitors voltage levels matched to lead-acid battery types and automatically switches on or off at specific levels.
We strongly advise against using this relay in conjunction with LiFe(Y)PO4 batteries, as the higher nominal voltage or working voltage range of lithium batteries is not compatible with the levels for lead-acid types.


en-flag Drawing
PDF, 78,44 KB
en-flag Manual
PDF, 1,05 MB

What other SVB customers have to say

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Stephen L.
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Have not installed the item as yet
Dietmar V.
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gute Verarbeitung
very good workmanship, fast delivery, very satisfied, gladly again
Andreas S.
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Alles bestens!
Price, performance, delivery time and communication - all the best! Gladly again!
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