SMC GVVZS300021A2 Motor Protection Circuit Breakers

Razz Middle East supplies motor protection circuit breakers for machine control panels in Saudi Arabia, sourced to order. A motor circuit breaker combines short-circuit protection, adjustable thermal overload protection and manual isolation in one device on the DIN rail. It replaces the fuse-plus-overload-relay arrangement in most modern panels, and it is selected against the motor it protects rather than against the supply.

SMC GVVZS300021A2

This page covers SMC part number GVVZS300021A2 — Motor Protection Circuit Breakers. Quote the full part number with your enquiry and the item is unambiguous: one part number identifies one exact product variant, including options that are not visible in the description.

About Motor Protection Circuit Breakers

Inside a motor protection circuit breaker there are two independent trip mechanisms. A magnetic element responds to short-circuit current almost instantly, and it is set well above the motor's starting inrush so that a direct-on-line start does not trip it. A thermal element, usually a bimetallic strip, responds slowly and models the heating of the motor windings, so it tolerates a start but trips on a sustained overload such as a jammed conveyor or a failing bearing. The thermal element is adjustable across a band, and the device is selected so that the motor's full-load current sits inside that band and the dial is then set to the actual nameplate current. That adjustment is the whole point of the device, and a breaker left at the top of its range protects nothing. Many of these units accept accessories in the same way a contactor does: auxiliary contacts for status feedback, trip-signalling contacts that distinguish a fault trip from a manual switch-off, undervoltage or shunt releases, and enclosures or rotary handles for door mounting.

Motor Protection Circuit Breakers in Saudi Arabia

Motor protection breakers are in every machine panel and motor control centre in the Kingdom: conveyor and crusher drives in cement, mining and aggregate plants, pump and blower starters in water treatment and district cooling, fan and compressor circuits in HVAC plant, and the individual drives on packaging and process lines in food and beverage. Panels run at 380/400 V, 60 Hz, and panel assembly is subject to SASO conformity. Two local factors distort the selection. Ambient temperature inside a cabinet in an unconditioned plant room shifts the thermal characteristic, so a breaker set exactly at the nameplate current can nuisance-trip on a hot afternoon while the motor is doing nothing unusual. And motors rewound locally sometimes no longer draw the current on their original plate, which makes a measured running current more reliable than the label. Repeated tripping is a symptom, and replacing the breaker without measuring what the motor actually draws just moves the fault.

Ordering and lead time

Identify the breaker from the device itself before ordering. Read the reference and the current setting range printed on the front, and photograph the label if the marking is faded. Then give us the motor data: full-load current from the nameplate, kilowatts, voltage and starting method, because the correct device is chosen so the motor's running current falls inside the adjustable band with headroom at both ends. Say whether accessories are fitted - auxiliary or trip-alarm contacts, a door handle, an enclosure - since they mount to specific frames and are ordered as separate references. If you are replacing after repeated trips, measure the actual running current first and tell us the figure, and we will check the selection rather than reproduce a part that may have been wrong from the start. Supplied on order, three weeks to site, delivered duty-paid.

Specifications are taken from the supplier's published catalogue data. Confirm against the manufacturer's current datasheet before ordering.