There is a signal light for each channel to clearly know which switch is working. Particularly suitable for the electronic circuit design of students in colleges and universities, can be connected with a single chip, or add a first level amplifier to drive a relay or a small DC motor.
eBay
DY-HL30T MP3 Power Voice Broadcast Prompt Module DC9-24V 30W High And Low Level Trigger Mp3 Playback
Aliexpress UK
Made of the high quality miniature optocoupler, anti‑interference ability, stable performance. Made of the high quality miniature optocoupler, anti-interference ability, stable performance. High/low level trigger can be switched.
eBay
30W power voice broadcast prompt module high and low levels trigger one-on-one MP3 playback TF card
Aliexpress UK
Each channel adopts optocoupler isolation, which has strong anti-interference ability. Trigger mode: low level trigger, high level trigger. There is an LED indicator on each relay switch. Material: PCB circuit board.
eBay
3V 1/2/4 channel relay module low level triggered luminous relay output relay module adopts 8550
Aliexpress UK
Trigger Mode: Low level trigger. When power on, the relay opens. T (T1 / T2 / T3 / T4): Trigger signal input (0.2-2 second low pulse). Item Type: Relay module. 1 x Relay Module. Supports simple installation, relay board with strong stability not requires particularly complicated operations.
eBay
1 Channel 5V 12V Relay Module Board Shield for Arduino with Optocoupler Support High and Low Level
Aliexpress UK
There is a signal light for each channel to clearly know which switch is working. Particularly suitable for the electronic circuit design of students in colleges and universities, can be connected with a single chip, or add a first level amplifier to drive a relay or a small DC motor.
eBay
Relay Module 1 Channel 5V 12V 24V Board Shield With Optocoupler Isolation Support High and Low Level
Aliexpress UK
Module can be set high level or low level trigger by jumper wire;. Trigger current 5mA;. Power indicator light (green), relay status indicator light (red);. High or low level trigger option Normally closed pin (NC1) : channel 1 relay normally closed pin.
eBay
1 2 4 8 Channel 5V/12V Relay Module Board Shield with Optocoupler Support High and Low Level
Aliexpress UK
There is a signal light for each channel to clearly know which switch is working. Particularly suitable for the electronic circuit design of students in colleges and universities, can be connected with a single chip, or add a first level amplifier to drive a relay or a small DC motor.
eBay
DC5/9/12/24V Single Channel Relay Module Smart Switch With Optocoupler Shield High/Low Level
Aliexpress UK
There is a signal light for each channel to clearly know which switch is working. Particularly suitable for the electronic circuit design of students in colleges and universities, can be connected with a single chip, or add a first level amplifier to drive a relay or a small DC motor.
eBay
5V 12V 24V 2 Channel Way Relay Module Board Shield with optocoupler Support High and Low Level
Aliexpress UK