ACCESSORIES FOR CHANGEOVER SYSTEM
Wire Interlock
Wire interlocks for 125A to 1000A frame models consist of two mechanisms connected by a cable. The mechanisms are mounted on two MCCBs located at a
distance from each other which is limited by the length and bend radius of the cable. The mechanisms and cable inhibit the closure of one MCCB unless the other
is in the OFF position. Each mechanism is ordered separately. Cables of 1.0m or 1.5m length are also ordered as separate items.
Wire interlocks can be used on a mixture of 3 and 4 pole MCCBs of different frame sizes. This allows potential cost savings by using lower rated MCCBs for the
alternative power supply. MCCBs can be mounted in different switchboard compartments or on different planes.
Wire interlock is an innovative design which will save space, time and money for switchboard builders in that:
• Installation is extremely simple. Wire interlocks are field-installable up to 1000A models.
• Wire interlocks replace the accessory cover on the front of the breaker.
• Motor operators and operating handles are compatible with wire interlocks.
• Interlocking of MCCBs mounted in different compartments is possible.
• No need to buy factory-built backplates with MCCBs and interlocks pre-fitted.
Wire interlocks are available also for 1250A and 1600A frame models.
The mechanisms are mounted on the back of two MCCBs. MCCBs cannot be mounted directly to a flat plate, but are installed on a frame to ensure space for the
interlock mechanism. (Factory Fit).
An important safety feature is that the interlocks do not allow a control system to close a second power supply on to a fault. If a breaker has tripped its partner
is mechanically prevented from closing. This differs from other interlocks you may be familiar with, which allow a breaker to be closed while its partner is in the
tripped position.
Changeover Pair with Wire Interlock and Motor Operators
Viewed from below of wire interlock with motor operator
Wire interlock operates according to the following table:
The electrical control system of an automatic changeover scheme which uses these interlocks should not attempt to switch the MCCBs to a combination
indicated as "NOT ALLOWED" in the above table otherwise damage to the motor operations will occur.
STATUS OF MCCB 1
STATUS OF MCCB 2
VALIDITY OF COMBINATION
ON
ON
NOT ALLOWED
ON
TRIP
NOT ALLOWED
TRIP
ON
NOT ALLOWED
TRIP
TRIP
NOT ALLOWED
OFF
OFF
ALLOWED
ON
OFF
ALLOWED
OFF
ON
ALLOWED
TRIP
OFF
ALLOWED
OFF
TRIP
ALLOWED
MSX
67
Informazioni Tecniche
Versione 2.0
Per informazioni tecniche contattate il SAT o visitate il sito gewiss.com
MCCB WITH THERMAL-MAGNETIC, ELECTRONIC, RESIDUAL CURRENT PROTECTION
AND SWITCH-DISCONNECTORS
MSX - MSXD - MSXE - MSXM
