Search
Search using google with ads
|
Search Search using google with ads |
Control water heater with temperature sensor |
 Digital controller... activated
by temperature probeProportional Integral Derivative/ PID control PID controller is activated by temperature-sensitive thermocouple or RTD. Use the PID to control any other circuit. Best to use PID to control a contactor or relay instead of directly connecting load to PID Use contactor or relay as shown in illustrations below ''Output actuator has a resolution of about 3%''. So if temp setting on PID is 140° then actual temperature is 140° ±3% or 4.2° margin of error. Using a separate contactor or relay that is rated for elements and motors allows millions operations without risk of overload and burnout of PID terminals. Buy: PID temperature sensor PID with relay output and thermocouple/ ITC-100HR/Temperature rang :-50～250ºC PID with SSR solid state relay output ITC-100V PID Temperature controllers Inkbird PID Digital temperature controller 30 amp contactors Omron relay Solid State Relay Board for Arduino Resources: Contactors Select breaker and wire size Inkbird .pdf Inkbird spec sheet |
|
 |
|
 Example PID thermostat wiring To use thermocouple (millivoltage input caused by heating thermocouple probe), connect thermocouple to terminals 4-5. Thermocouple is 2 different metals joined together that create small electric current when heated. PID interprets changing flow of electricity as change in temperature. Thermocouple can take time to cool down after circuit turns off. Water likewise takes time to cool down. Ordinary water heater thermostat is mechanical. Two different metals are joined. The metals expand at different rates and bend when heated, creating a switch that toggles one direction when heated, and bends back after cooling. To use RTD (resistance caused by heating RTD sensor): When connecting three line RTD sensor, #3 terminal is for red wire, #4 and #5 are for other two blue lines. For some sensors, #4 and #5 terminals should be connected together. RTD best for -100 to +500°F RTD is a variable resistor that limits milliamp (current) flow through the RTD. PID interprets change in resistance as change in temperature. RTDs are superior to thermocouples in that their readings are more accurate and more repeatable. Repeatable means that users reading the same temperatures produce the same results over multiple trials. Check input and output voltage before buying PID Max water heater temperature for residential heater 210° before TP releases water. Maximum temperature setting for residential water heater thermostat 150°, ideal tank thermostat setting 120° for residential heater, typical bath shower 104°, danger from scald begins at 140°, temperature for killing bacteria 140°, Thermocouples can be used to measure up to 2700 degrees Fahrenheit. Check control and output voltage before buying PID Buy: PID with relay output and thermocouple/ ITC-100HR |
|
 General information on PIDWiring on this page requires PID with relay output, and voltage rating 120-240 volt. The relay output includes terminals 8-7-6, with terminal 7 the COM, and 6 and 8 the switching terminals NO and NC.... (normally open, normally closed) Output relay max 3 amps ... sufficient to energize contactor. Add 3 amp line fuse to protect PID from 30 amps that ave available on the water heater circuit. Thermocouple is accurate for water heater. For more precise control of temperature, an RTD can be used. Buy: PID with relay output and thermocouple/ ITC-100HR Panel mount fuse holders at Amazon ANL fuseholder Fuse blocks at Amazon Din rail fuseholder 10 x 38 mm fuse Ceramic fuses at Amazon Fast acting ceramic fuses Electrical terminals |
 |
Buy
from my affiliate links every time/ thanks: Amazon ''As an Amazon Associate I earn from qualifying purchases'' Enter Amazon from any link on my site, fill cart with any item ... purchases pay small commission E-mail: geno03245w@gmail.com My response might end up in spam folder, check email folders Waterheatertimer on Twitter Message thru facebook |
