Magnetic Switches and Annunciators
Tattletale annunciators and magnetic switches are the nerve centers that translate gauge contact operations into decisions and operate the alarm or shutdown device.
- Operates from battery power, 120 VAC, conventional magnetos and capacitor discharge type ignitions
- Weather-resistant case with screw terminals for ease of customer hookup
- Manually reset models have a face-mounted reset push button which also serves as a fault indicator
- Time delay models allow operation of alarms before shutdown occurs
FW Murphy Production Controls offers support for all our products. If you are unable to find the product that you need, please call us at 918-957-1000.
These switches are the electrical load-carrying devices for the alarm or shutdown device. Tattletale annunciators indicate which monitored function failed leading to the alarm or shutdown; magnetic switches do not. Magnetic switches operate basically as a latching relay.
Application
Magnetic switches and Tattletale annunciators are available for use with engines or electric motors. Various circuits, time delays and contact configurations are available to match the power source and mode of operation required for alarm only, alarm before shutdown or shutdown only.
For distributor ignition engines, the magnetic switch opens the distributor coil circuit to cause shutdown. For magneto or CD ignitions, the magnetic switch grounds the ignition output. Some models can also trip fuel valves instead of or in addition to grounding the ignition. Diesel engines are shut down by either closing off the fuel or air supply. Magnetic switches and Tattletale annunciators can make or break circuits for these engines.
For electric motor applications, various magnetic switches are available to operate the motor starter, holding coil directly or in conjunction with appropriate Transformer-Relay assembly.
Features
Magnetic switches and Tattletale annunciators described are electrically tripped relay type devices. Models are available to operate from battery power, 120 VAC, conventional magnetos and capacitor discharge type ignitions.
Energized to run models allow Closed Loop circuitry. Others draw momentary power to trip. Configurations are available for contact make or contact break to cause shutdown. Some models have both make and break contacts.
All models have a weather-resistant case with screw terminals for ease of customer hookup. Manually reset models have a face-mounted reset push button which also serves as a fault indicator in the Tattletale version. In this application, one or more Tattletale/magnetic switches are used to advise operating personnel which monitored function caused shutdown.
Only the Tattletale connected to that function sensor trips causing the reset push button to pop out.
Electrically reset models perform the same functions as the manually reset models and are reset by cycling the power supply off and then on.
Time delay models use reliable solid state time circuits to lockout operated switch contacts for start-up and/or to allow operation of alarms before shutdown occurs. Specific models allow application of power to a shutdown circuit and automatic disconnect of power after a given time delay.
Coil Voltage:
- 12 volt
- 518PH
- 518APH
- 760A ‡
- 24 volt
- 518PH
- 518APH
- 760A ‡
- 12/24 volt *
- 117
- 117PH
- MS2110
- MS2111
- 822PH
- 120 VAC
- MS2100
- Magneto ignition
- MS2120
- M4264-1CD
- CD ignition
- MS2100
- M4264-1CD
* Multi-voltage AC or DC systems. See circuit descriptions below.
‡ Does not latch after shutdown signal clears, automatically resets.
Coil Resistances (OHMS):
Product – Coil Resistance in OHMS, or coil and resistor
- 117 – 18
- 117PH – 18
- MS2100 – 288
- MS2110 – 18
- MS2111 – 72
- MS2120 – 0.5
- 518PH – 339/678 for 12/24
- 518APH – 339/678 for 12/24
- 760A – 90/190 for 12/24
- 822PH – 30
Contacts (see Note 2 below):
- NCH
- 117
- 117PH
- MS2100 (A)
- MS2110 (A)
- MS2111 (A)
- 518PH
- 518APH
- 760A
- 822PH
- NOH
- MS2100 (A)
- MS2110 (A)
- MS2111 (A)
- 518APH
- 760A
- 822PH
- NCG
- MS2120 (B)
- M4264-1CD (B)
- NOG
- MS2120 (B)
- M4264-1CD (B)
(A): Dry contacts normally wired in hot circuit
(B): Dry contacts normally wired in ground circuit
Latch Type:
- Energize to trip
- 117
- 117PH
- MS2100
- MS2110
- MS2111
- MS2120
- 760A
- 822PH
- M4264-1CD
- Energize to latch
- 518PH
- 518APH
Reset Type:
- Manual indicating
- 117PH
- MS2100
- MS2110
- MS2111
- MS2120
- 518PH
- 518APH
- 822PH
- M4264-1CD
- Manual non-indicating
- 117
- Electric non-indicating
- 760A
Time Delay:
- Before shutdown
- 760A
- Start only
- 760A
NOTES:
The information above indicates features/configurations available for each model.
1. Coil Voltage – Coils are specific voltage rated or multiple voltage rated.
2. Contacts – This is the control circuit output. In the lathed position, the NCH contact has a hot output. In the latched position, the NCG has a grounded output; in the tripped position, the NOG has a grounded output.
3. Latch Type – Refers to whether the magnetic coil is momentarily energized to trip or requires continuous power in the operating mode and de-energize to trip.
4. Reset Type – Refers to manual or electric reset; manual indicating type is a Tattletale.
5. Time Delay – Indicates operation of the time delay.
6. Coil Resistance – In OHMS or coil and resistor:
1.(0.5), 2. (18), 3. (30), 4. (72), 5. (90/190 for 12/24), 6. (288),
7. (339/678 for 12/24), 8. (339/618 for 12/24)
117/117PH/117PHF
MS2100
MS2110
MS2120
518PH
518APH
MS2111
760A/760AF
822PH
M42641CD
For more information about this product, you can download the related literature here: