The Victron Energy SolidSwitch 104 is a solid-state DC load switch rated up to 70V / 4A that you control with a low-power digital signal. It's the best-fit solution for Victron lithium system owners who need to switch DC loads or drive an external alternator regulator without the current draw of a mechanical relay. Buy online today for $23.60 — a 50% discount off the $47.20 compare-at price.
Wiring the SolidSwitch 104 to a BMS Allow-to-Charge (ATC) Output
Connect the BMS ATC output to the SolidSwitch control input. The SolidSwitch's control circuit draws a maximum of only 0.1 mA, so it won't burden the BMS signal. Its switching contact then drives the charger(s) or other DC device — and you can use multiple SolidSwitches to increase the number of chargers wired to a single BMS ATC output.
Can It Control an External Alternator Regulator?
Yes. In a Victron lithium system the SolidSwitch 104 is commonly used to switch the external alternator regulator on and off based on the BMS signal.
How Much Current Does It Draw?
The control side draws a maximum of 0.1 mA — about 0.04 Ah per month. A comparable small mechanical relay can consume 10 Ah per month, so the SolidSwitch preserves battery capacity between charges.
Specifications
Product Details
- Brand: Victron Energy
- Model: SolidSwitch 104
- Product Type: Solid-state DC load switch (Power Accessories)
- Load Rating: Up to 70V / 4A
- Control Draw: Max 0.1 mA (≈0.04 Ah/month)
- Use: DC load switching, external alternator regulator control, BMS ATC signal expansion
Selection Criteria & Alternatives
Choose the SolidSwitch 104 when control-circuit current must be minimal and loads are within 70V/4A. For higher-current loads, use it to drive a larger contactor — the solid-state switch controls, the contactor carries the load. Compared to mechanical relays, it wins decisively on standby consumption and reliability (no contacts to wear).
Use Cases
- Allow-to-charge signaling between a Victron BMS and multiple chargers
- External alternator regulator control in lithium systems
- Low-power DC load switching such as lighting
Price Value & Deal Value
At $23.60 vs. $47.20, you save $23.60 (50% off). Apply coupon OUTPOST12 for an extra 12% off. Free shipping on orders over $45.00 — pair with a second SolidSwitch or other Victron gear to qualify.
