Timer and Counter Modules
U1 CD4541 is a Timer with Long Duration Ability. This timer is started by a low pulse from earlier circuit, when the temperature goes above setpoint, a low state is at U2A inputs, this...
Category: Industrial-Automation
RS485 Modbus – Wireless Interface
I am working on alarm systems and would like assistance in designing wireless link for the unit, ie sensors to control panel, control panel to monitoring station. I noticed most of the circuits available...
Voltage to Current Convertor using LM723
his Circuit converts a voltage control output from a Process Controller to be converted into a Current Control if the AC-Drive or Valve needs a Current Control Signal.. Significance of Current Loop 4 to...
Significance of Current Loop 4 to 20 mA Standard
Subject: delabs comments – Tell Me. message: why 4-20mA standard. why not 2-22mA or any thing else Mail from MU they knew you would come up with a question like this. so see this...
Temperature Meters with Analog Recorder Output
I would like to know if you offer a monitoring solution that will constantly measure ambient (air) temperature (say, 0 to 150°F), and provide a corresponding DC voltage output of either 100 mV, 1...
Presettable Up-Down Counter Timer
When i had put the near Obsolete digital circuits online in the late nineties. One person who works in a public institution in the usa, wanted a modification of one of my existing circuits....
Speed control with TDA1085 – PCBWay
This is a Sponsored Post, The contributions from these Sponsor Firms help enhance and improve the delabs websites and services. The speed controller of collector motors on the TDA1085 chip still remains popular among...
BCD Thumbwheel to Voltage Interface
This is a Proportional Controller where the setpoint is derived from a Thumbwheel switch. The conversion of Thumb-wheel Digital Data to Analog mV is similar to R-2R Weighted Resistor Network. In this case it...
Millivolt Source – Field Calibration Current Loop
This is easy to rig millivolt source for field calibration or troubleshooting of 4-20 mA current loops. Here a Darlington pair is used for current amplification which reduces the Ib error as gain is...
DC-DC SSR Solid State Relay
This is a DC Input DC Output SSR Solid State Relay. It was made for Printing or Photo Processing Equipment. It has an optical isolation and can be used for inductive loads. The R1...
InfraRed Detector for Proximity Switch
The proximity switch can work for a wide range of power, from 8v to 18v DC, D3 protects reverse power supply connections, and U1 regulates the supply to +5v , -5v is derived from...
Timer and Counter for RTD System
Thank you for your assistance. My answers are by your questions. Hope this helps. This unit is more for troubleshooting a air flow problem. If the counter shows many 130 Degrees detected or alarm...
