Arduino Compatible 5V Relay Board - General Electronics - Arduino Forum

I am having trouble with relay board and wonder if anyone could assist I have wired the relay supplying 5VDC from the Arduino Uno and switching from digital output. I am seeing a volt drop on the switch measuing 4VDC. When disconnected I have 4.8 VDC. The arduino is being feed from 9VC connector supply from a car battery through a 1Amp voltage regulator. If i connect the switch wire to Common 5VDC the switch will operate.

5v Relay Module help - General Electronics - Arduino Forum

help with 5v 8 channel isolated relay - General Electronics - Arduino Forum

Relay triggers onwantted on startup - General Electronics - Arduino Forum

How to use this 12V Relay with Optocoupler? - General Electronics - Arduino Forum

Duinotech relay wiring - Motors, Mechanics, Power and CNC - Arduino Forum

How to read Voltage through Arduino - General Electronics - Arduino Forum

Confused about a schematic for controlling relay that I found - General Electronics - Arduino Forum

How to Control Bulb by Using Arduino UNO and Single Channel 5V Solid State Relay Module : 3 Steps - Instructables

problems with 5 volt relay module - Project Guidance - Arduino Forum

NodeMCU with 5V relay - General Electronics - Arduino Forum

SunFounder 2 Channel DC 5V Relay Module with Optocoupler Low Level Trigger Expansion Board Compatible with Arduino R3 MEGA 2560 1280 DSP ARM PIC AVR STM32 Raspberry Pi : Electronics