TWTADE SSR-40 DD 40A DC 3-32V to DC 5-60V SSR Solid State Relay + Heat Sink

It has been working very well since I installed it in 2023. The wiring was straightforward and it has remained stable during continuous use. I haven’t experienced any failures or overheating. Good quality for the price. I would definitely buy it again. ⭐⭐⭐⭐⭐

I have two of these in enclosed but outdoor locations. Working well after over a year.

I'm using two of these to control a 110v 1300watt heating pad that draws around 11amps and a 110v 550watt 5amp 635cfm exhaust fan. I havent ran the heating pad yet, but the fan does great. I have the heatsinks cooled by a 24v fan and 150c thermal fuses fixed to both of them in case they fail. If I ever have any issues, I'll report back with updates. Edit: I guess I should mention I'm triggering them with 24v DC off of a PSU. Low voltage side is negative from the SSR to the negative on the PSU and positive from the PSU to a switch to the SSR. 110v side interrupts the LINE wire for the exhaust fan.

This relay caused me hours of scratching my head. I am using it in a Tesla and i'm thinking something is wrong with the car. Come to find out that even though the circuit I chose to activate this was working properly, this relay stayed on and allowed the power to go through what is supposed to be open contacts. Instead, the ohm reading is 372k ohms of resistance which is enough to keep the led lights I used to stay on all the damn time. This wiring was all in an enclosed space so it's kind of a pain in the butt to deal with. I ended up tapping off of another circuit and using a standard relay for now just to have things working. I only had it wired for 2 days. The voltage going to it was between 8 and 15 volts dc and the load was probably an amp at 15 v dc. This was well within the range listed.

I have about twenty of these built into temperature controller boxes now. They run almost continuously at around 50% duty cycle average for the last year or so. They are switching only about 2A of resistive current (on the 40A rated units) and they stay cool. They have been mostly reliable, but we have had a few fail. The ones that have failed have failed because we connected a shorted heater. A 15A fuse has proven insufficient to protect the SSR from this happening. When they have failed due to a short circuit, they have failed CLOSED, which is bad. This could be a big problem, depending on your application. Please keep this in mind!! Ultimately, the devices are cheap enough to consider an expendable, like a fuse. Just keep in mind that they seem to fail shorted and they are fairly delicate. I personally wouldn't run more than about 10A on the 40A rated ones.

I use it in the garage ceiling to control multiple LED light bulbs from the light output of the garage opener. It works reliably for a year now. As one may know, if you use LED bulbs for the garage opener light, it decreases the range of the openers (if they work at all) and in time it will burn the internal wireless controller of the garage door opener. The solid state relay I use it as a 'separator' to route the AC circuit of 3 LED bulbs directly from the 120V house circuit and command it with the garage door opener. I mounted it in the garage ceiling and almost forgot about it. Now my garage openers range from the cars is more than 150 ft.

We used this to create an additional safety shutoff for a mobile solar power system. Our control circuit measures the battery voltages, and if any are over the tolerance setting, it cuts a small relay that then cuts power to this unit. This unit then faithfully disconnects the solar input, effectively preventing over-charging and increasing overall system safety. Unit has been in use consistently for several months now and has performed reliably. Our load is much smaller than it's rating though (about 10 Amps at ~30 volts), but the unit does not appear to get warm even while handling this.

They do what they say, but they get very hot.