cnzhihuizai Wired water sensor Relay dry contact signal output Water level sensor DC12V power water detector Applicable to the equipment room and base station

When this sensed water, I was able to hear the faint sound of a relay clicking inside the housing. To completely rule out any solid state switch, I tested, and confirmed, zero continuity between power (Red 12V) and Blue/Green/Yellow, and ground (Black) and Blue/Green/Yellow. I was hoping to use this as a float switch, or pumping water out of a condensate tank. Unfortunately, it can't be used for that purpose. It would drain down to the threshold of the switch, the pump would go off, a tiny amount of water would flow back, and the switch would oscillate rapidly between on and off. This is really designed for alarm usage, rather than level control. Still, it's an awesome product. It triggered on a wet napkin, so the probes are quite sensitive. The probes are just 0.085" from the base, so this will trigger when the water level is 0.085". You might have better luck on a carpet, because the carpet fibers could wick the water up to the probes faster. On a level hard cement floor, 0.085" of liquid is actually quite a bit. Ironically, my basement just flooded, 2 days ago, and lots of damage happened before the level got that high. If that is your intended application for this sensor, I would use a grinder to wear down the base until it is nearly level with the probe tips. That would still leave you with a 0.035" gap on the four gaps/slots, in the housing, for water to sneak in. Or, I would get one of the probed that has an open housing, so you can get the probes to physically touch the floor. That would be a much better choice. Since this is a weighted sensor, I suspect it was invented specifically for tossing into a tank, or chemical drum, and automatically leveling itself out on the bottom. The bell-shaped flange, on the bottom, makes it so this would always land probe side down. Enjoy.

I got this for use as a level control to manage pumps in my water system, and it works well with a little more wiring than a traditional float switch. It would be simpler to install as an alarm sensor, since the relay is only rated for .5-1A current. I used this sensor relay to latch another relay which can then power my pump. The sensor is well constructed and heavy. The zinc alloy housing is well potted and the waterproofing looks durable. I question the choice of zinc since it is used as a sacrificial anode and it might dissolve over time if exposed to salt water in a marine environment. The attached wire is under 5', which could force a waterproof splice if used in a deep tank, but it is designed to install through a mounting hole in the tank with the wiring remaining outside the liquid. For the designed application, this should last and provide good safeguarding from water intrusion and avoid costly water damage. I'm a little surprised that the internal relay has such a low current rating. The included instructions provide good details for wiring and usage. This feels like a quality sensor and I expect it to be reliable.

There are a lot of sensors in the industrial world that are active sensors, they either provide a high-going output (positive voltage) or a low-going output (grounded when activated). The disadvantage of these sensors is some control systems may not natively accept the signals produced by those sensors. This sensor separates itself in that regard as the water intrusion output is a dry contact that offers both NO and NC contacts. This allows you to use whatever type of input your control system uses to accept this sensor without any additional adapters. The sensor works perfectly on a floor to indicate water intrusion. There does seem to be some discrepancy on the clearance of the sensor pins to the surface of the flange. My sensor measured 0.07" from the pin edge to the flange, which is acceptable for my application. Judging from the pins being slightly tilted on my sensor, I am going to hazard a guess and say the clearance will widely vary here. You may want to check this on your sensor before commissioning. The flange does have plenty of material to setup a better clearance if you need to. The sensor itself is instantaneous responding when there is liquid continuity between both sensing pins. As soon as that continuity is lost, the sensor returns to its normal state. This is a great instrument for alerting to water intrusion in areas sensitive to flooding.

I ordered this product to monitor a wonky sump float that has been having some intermittent issues triggering its discharge.Paired with a piezo buzzer and 12v LFP battery, the relay is a slam dunk. As another reviewer points out, the sensor's internal components are encased in resin through which its probes protrude. Resin encasement under vacuum absolutely guarantees a waterproof product and is not a cheap process.It is ultra sensitive, and will trigger my buzzer with damp towels, paper etc., but not so sensitive that humidity alone would fire the relay.Overall, this product has exceeded my expectations in construction and performance. Easy 5 stars.

This sensor is well made from quality metal. The sensor has wiring that provides for a normally open or normally closed contact that if activated will send out a signal to the host for appropriate action. These type of devices are particularly great for a vast array of applications in which there is some type of water source in an upper floor that if leakage were to occur one would want to know it before further and significant damage may occur. The seller provides easy to understand and follow instructions and the item is as described. Installation is easy and straight forward for those familiar with these type of products. I am very pleased with this item and believe you will be as well. Therefore, Dr. T. highly recommends this product!!