Apex optical board
This assembly will work with most 4 pin "Optical Infrared Water Liquid Level Sensor" sensors available on eBay and Amazon. Below shows the type of sensor you should use. Make sure the sensor operates at 5V.
With the sensor connected to the PCB and the PCB assembly connect…
Apex optical board
This assembly will work with most 4 pin “Optical Infrared Water Liquid Level Sensor” sensors available on eBay and Amazon. Below shows the type of sensor you should use. Make sure the sensor operates at 5V.
With the sensor connected to the PCB and the PCB assembly connected to your apex using the supplied DIN 8 cable, plug in the 5V supply to the assembly. If the optical sensor is DRY, the apex will show CLOSED for the associated switch. If the sensor is WET, the apex will show OPEN. You can use a standard contact switch (float) in parallel with each of the 5 optical ports as a safety backup as long as the contact switch is NO (normally open) to allow the optical sensor to function first. All 6 ports can be used as a normal switch input if optical sensors aren’t needed or in any combination. Port 6 is only contact switch.
Note on sensor mounting. We have found the best performance is to mount the sensor horizontally. This allows water to drip off the clear lens easier and react faster. Pointing straight up works as well but could collect water on the lens. The least preferred method is pointing down since water can sit on the tip of the lens and delay triggering.
BOM:
Install 390 ohm resistors to positions R1-R5 (P/N CF18JT390R)
Install 6.8k ohm resistors to positions R6-R10 (P/N CF18JT6K80)
Install diodes to positions D1-D5 (P/N 1N4004), note the end with the silver marking must be positioned with the marking on the PCB
Install the 5 4 pin headers to J2-J6 (4-Pin XH2.54 2.54mm Shrouded Header, source EBAY)
Install the DIN 8 connector at P1 (P/N MD-80SM)
Install the power supply connector at J1 (3 pin DC 2.1 Power Jack Female PCB Socket Plug 5.5*2.1mm, source EBAY)
Install the 12 port header to J7 (P/N OSTTC120162)
Power supply: https://www.amazon.com/gp/product/B00GUO5WUI/ref=oh_aui_search_asin_title?ie=UTF8&psc=1
PM1/PM2/APEX to board cable: https://www.ebay.com/itm/6ft-Mini-DIN-8-Pin-M-M-Male-to-Male-Beige-MD8-8-MiniDIN-MDIN8-Cable/301756594107
Optical sensors: Look on ebay or amazon for any generic 4 pin optical sensors. Note: they typically aren’t the greatest quality so pick up a few spares.
