Schneider Electric 47894 MCH Motor Mechanism 200-240 V AC

47894: MCH motor mechanism, 200 to 240 V AC

The 47894 is a Schneider Electric gear motor, short name MCH, a motor mechanism for automatic spring charging on MasterPact NW circuit breakers, rated 200/240 V AC 50/60 Hz. The datasheet also lists it for EasyPact MVS breakers. Seven Star LLC supplies the 47894 in Oman and the GCC as an independent supplier based in Muscat.

A stored-energy breaker closes using a spring that must be charged first. The MCH motor mechanism charges that spring electrically, so after every closing the spring is recharged automatically and the breaker is ready for another operation within seconds. Without it, charging is done by hand with the breaker’s lever.

Technical specifications of the 47894

How the 47894 charges the closing spring

The motor drives a gear train that winds the closing spring of the breaker. The datasheet gives a maximum charging time of 4 seconds and a maximum operating frequency of three cycles per minute, which together describe the practical limits: the spring is recharged in at most 4 s, and the mechanism is not intended for faster repetition than three charge cycles a minute.

The supply tolerance is stated as a threshold tripping voltage of 0.85 to 1.1 x Un. For a 230 V control supply that corresponds to about 195 V to 253 V (calculated). A control supply that sags below the lower figure when the motor starts will give slow or incomplete charging, so the voltage should be measured at the terminals under load.

Supply and power for the 47894

The maximum power consumption is 180 VA at 200/240 V AC, which is the figure to use when sizing the control transformer or the circuit-breaker for the motor supply (about 0.75 to 0.9 A, calculated from the VA and voltage). It is a maximum figure, so a measured value will usually be lower.

The datasheet lists AC only for this reference. A plant with a DC control supply needs a different motor-mechanism reference, so state the supply type clearly when ordering.

Compatibility and where this motor does not fit

The datasheet lists MasterPact NW and EasyPact MVS circuit breakers as compatible. It does not list ComPact NS breakers, which are molded-case devices with a different operating mechanism; the NS breakers that Seven Star LLC handles, such as 33482 and 33570, are operated by toggle or rotary handle and are not fitted with this part.

For a MasterPact NW installation the MCH is usually paired with an MX shunt release and an XF closing release so the breaker can be opened and closed remotely. Those are separate part numbers; MX releases such as 33662 are listed for NW, with a response time of 70 ms.

Fitting and maintaining the MCH

Fitting the 47894 is a job for a qualified technician with the breaker withdrawn or fully isolated. After fitting, connect the supply, check that the motor charges the spring and that the breaker’s charged indicator shows, then close and open the breaker several times and confirm that recharging happens each time within the 4 s limit.

Because the motor winds the spring after each closing, the number of charge cycles increases the wear on the gear train. Record the operating count, listen for changes in charging sound and consider replacing the mechanism as part of a breaker overhaul rather than waiting for a failure.

Where it is used in Oman and the GCC and why it matters

Automatic spring charging is standard on larger incomer, bus-tie and generator breakers in power stations, desalination plants, oil and gas facilities and large industrial buildings across Oman and the GCC. It enables remote closing from a control room and automatic changeover schemes, where nobody is present to wind a spring by hand.

Hand charging works, but it ties closing to a person standing at the breaker. With a motor mechanism, the closing command can come from a control room, a synchronising relay or an automatic transfer scheme, and the breaker is ready for a reclose within a few seconds because the spring recharges straight away. The cost is a control supply of up to 180 VA per breaker and one more wear item in the mechanism.

When a project lists breakers, motor mechanisms, shunt releases and auxiliary contacts as one package, the safest route is to match each accessory to the exact breaker nameplate; the datasheet range listing is the check for this part. If the nameplate is unreadable or the breaker is an older generation, send us what you have and we will confirm compatibility before quoting.

Selection checklist for the 47894

• Breaker: MasterPact NW or EasyPact MVS, not ComPact NS.
• Control supply: 200/240 V AC 50/60 Hz.
• Remote control scheme: whether MX and XF coils are also needed.
• Operating pattern: no more than three charging cycles per minute.
• Quantity and delivery location.

Information to send with an RFQ for the 47894

Please send the part number 47894, the quantity, the breaker type and nameplate, the control supply voltage and frequency, and the delivery location in Oman or the GCC.

Documents and quotation

The official English datasheet for the 47894 is attached on this page. It lists the supply voltage, charging time, operating frequency, power consumption and packaging data.

To request a quotation, send the part number 47894, the quantity and the delivery location. Seven Star LLC is an independent supplier in Muscat and quotes according to current availability.