#63-1/2, H1: AC Voltage Detector


Function: 110V AC (#63-1) or 220V AC (#63-2) voltage detector

Form factor: H1

Category: Input module

Special needs: [INT] (optional)

Power requirements: 5V/12mA

Temperature range: –40°C to +85°C

Mates with: ---

See also: #15



This Tibbit is based on the MID400 AC line-to-logic optocoupler. AC voltage detection is particularly useful when integrating old contactor-based control systems into digital management systems, such as detecting and reacting to blackouts or monitoring AC feedback lines to ensure power delivery in mission-critical applications.

Tibbit #63 comes in two versions: #63-1 and #63-2.

Tibbit #63-1 is designed for use with 110V AC lines (also referred to as 120V AC). Due to its low detection threshold, it can also monitor 24V and 48V AC voltages, which are not uncommon in contactor-based control systems.

Tibbit #63-2 is primarily designed for use with 220V AC lines (also referred to as 230V or 240V AC), but will also reliably detect the presence of 110V AC power. Due to its higher detection threshold, this Tibbit is not suitable for monitoring 24V AC lines. We recommend choosing #63-1 for all low AC voltage needs.

The MID400's output is exposed on the Tibbit's –DETECT pin (Line D). The line goes LOW when the AC voltage exceeds the "on threshold" (see the table below). The line is set to HIGH when the AC voltage falls below the "off threshold."

When connected to a Tibbo Project PCB socket with interrupt capabilities, changes to the –DETECT pin can generate interrupts. The use of an interrupt line is optional — you can also poll the –DETECT line.

Tibbit #63-1/2 Specifications


Tibbit #63-1

Tibbit #63-2

Maximum AC input current

5.5mArms @ 110V

6mArms @ 220V

AC voltage detection — on threshold

~19Vrms ±5%

~40Vrms ±5%

AC voltage detection — off threshold

~18Vrms ±5%

~36Vrms ±5%

5V current consumption, LED off


5V current consumption, LED on


Operating temperature range*

–40°C to +85°C

* Tested according to procedures I, II, and III of MIL-STD-810H Method 501.7 and MIL-STD-810H Method 502.7.


There is a single green LED, which lights up when Line D is LOW (AC voltage detected).


Tibbits #63-1 and 63-2 are designed to detect high AC voltages. Improper handling of high AC voltages may lead to property damage, injuries, and even death. By using Tibbits #63-1 and 63-2, you explicitly agree not to hold Tibbo liable for any damages, injuries, or death arising from the use of these Tibbits.