Simplex 4060-8 Help

I recently purchased a Simplex 2093 light+4060-8 bell combo. The light is 24VDC, but the bell is 1.3. Can someone please explain this?

The 24 volt light needs no explanation. The bell is from a system using a series signal circuit. What is the rest of the information on the data plate on the bell?

The bell is probably a single stroke type which is used on a coded system. An example of a system that would use these is a 4208 with type “L” signal modules.

It’s a DC bell, so that’s why I posted. If it were AC, I wouldn’t have.

The bell operating current is probably listed somewhere around 2.5 amps.

Yup. I just didn’t know that DC alarms could be wired in series.

So 5 bells would be about 6V@12.5A?
Link to photo

No. One of the rules of electronic circuits is that the current is the same at all points in a series circuit. It would be 6 volts 2.5 amps.

Could I run a single bell off a regular AA battery or would the bell require too much current?

You can try it. Might work it a few times. 2.5 amps is a big current hit to an AA battery so it will not last very long.

Would the extra .3V harm the bell or is it too minimal?

The extra .3 volt should not be a problem. That 2.5 amp coil is wound with big enough wire to take that for a while. Besides, the battery voltage will sink down pretty fast at 2.5 amps.

Do you have any suggestions while I wait to “rescue” other 1.2V bells from an abandoned building?

The only other way to operate these bells is from a power supply that can EASILY put out 2.5 amps. The basics of the 4208L module are a hefty power supply capable of operating 2 circuits, a control circuit board, and a compensating rheostat for each circuit. The rheostat compensated for a lesser number of series bells than the maximum. A DC ammeter was put in the circuit and the rheostat was adjusted for 2.5 amps flowing in the circuit when activated.

If you have a suitable power supply (24 volts or 12 volts) that can handle 2.5 amps and a meter that can measure that amount of current this can work. Obtain a 10 ohm (a 12 or 15 ohm will work too) 25 watt or 50 watt rheostat. I have seen them on Ebay and Amazon. Hook it all up with the rheostat in series as if it is another bell and the DC ammeter in series too. Set the rheostat to maximum resistance. Then power up the circuit. Adjust the rheostat until you get 2.5 amps on the meter. Since these are single stroke bells it will only make one ding. These bells were made for coded systems so they make a single ding each time the voltage is applied.

Would maximum resistance be all the clockwise or all the way counterclockwise?

A rheostat is a 3 terminal device, but in this application only 2 terminals are used. The center wiper terminal and one of the end terminals. So you get to decide which way you want maximum resistance to be when you wire it up. Maximum resistance will be the position where the wiper is turned farthest away from the end terminal with the wire connected.