Heater Burn-out Detectors

Heater 'Burnout' Detector


Single and 3-phase

Stalled Motor Detector
Self powered (When current is above 5A)

BO Detector Series Burned out heater elements cost time and money to diagnose. Don't let them cost you down time. Get the Burnout detector! Unique self-powered design saves complexity and wiring time. The burnout detector works by sensing the AC current and activating at the specified set point. Sensing a repeatable specific trip-point, allows the burnout detector to monitor multiple parallel connected heater elements. The BO series can detect stalled motors by sensing the out of range current. In 3-phase operation (using a delta or 4-wire-Y configuration), of the Transtronics Burnout detector allows one sensor to monitor all three phases. Upon detection, it lights the LED and optionally activates an output. Four basic output versions are available: LED lamp only, open collector, Triac and form C relay. Options include: large pass opening, adjustable set-point and remote mounting LED.


Standard 0.875" Opening



Set point current range (specify with order)

to 1KA (When setpoint is below 5A 5Vdc must be applied to pin 3)

Set point accuracy

+/-15% (5% on adjustable units) 10% dead-band

Output current Relay option

4A @ 220 Vac 5A@30Vdc/120Vac see drawing below for pin out

Triac output version

2A @ 220 Vac

Transistor output option

20 mA 24V (Pin 8 negative.; Pin 6 positive)

Ambient Operating Temperature

0 C to 60 C

Octal Case Size

2.75 X 1.75 X 2.375 inches (excluding octal pins)

Pass through opening

22.2mm [0.875"]

Adjustable versions available

Relay power supply

12V or consult factory

[] - denotes legacy units



Wiring Diagrams


One or 3 Wire(s) with Ac current are threaded through opening.
No electrical contact is made with the current carrying wire

Remote mount LED wiring Pin 2 goes to + (plus) or the long lead
Pin 4 goes to - (minus) or the short lead. No dropping resister is required
Remote mount LED is not compatible with Triac version

Din rail mountable bases are available as an accessory

Let Transtronics help you with your application. We want to help you solve your automation problems.

For Pricing call 785 841 3089 (most versions are less than $100)

Order number Description


LED only


Self powered Transistor output


With self powered 2A Triac output


4 A Form C Relay output - requires external power


Adjustable set point option


External 24 power to LED (Pin 7) option


Din-rail/panel mountable octal base accessory


This information may have errors; It is not permissible to be read by anyone who has ever met a lawyer.
Use is confined to Engineers with more than 370 course hours of electronic engineering for theoretical studies.
ph +1(785) 841-3089 Email inform@xtronics.com

(C) Copyright 1994-2017, Transtronics, Inc. All rights reserved
TranstronicsĀ® is a registered trademark of Transtronics, Inc.
All trademarks are the property of their respective owners.