Mersen NH2AM69V200 NH2 aM 200A 690V Motor Fuse-Link V227971

NH2AM69V200 (item number V227971) is a Mersen NH fuse-link of size 2, type aM, rated 200 A at 690 V ac with 80 kA ac breaking capacity, double indicator and live gripping lugs. The aM characteristic is intended for motor-circuit short-circuit protection.

Motor-circuit short-circuit protection at 690 V

Mersen describes aM fuse-links as partial-range breaking-capacity devices used to protect motor circuits: they are strongly current-limiting with low power losses and interrupt currents from 6.3 times In up to their maximum breaking capacity, so they give short-circuit protection only and must be combined with other switchgear (for example a contactor with overload relay) for overload protection. The rated current can equal the motor’s nominal current.

The 200 A item dissipates 11.3 W at rated current (compared with 18.5 W for a gG 200 A fuse in the same body in the gG datasheet), weighs 0.64 kg and is packed three to a box. Its 690 V rating suits 400/690 V motor systems.

Key features as printed in the datasheet

• Size 2, aM, 200 A, 690 V ac; 80 kA ac breaking capacity.
• Double indicator; non-isolated gripping lugs; 0 % cadmium.
• Partial-range: interrupts from 6.3 x In; short-circuit protection only.
• Power dissipation at In 11.3 W; weight 0.64 kg; width 52 mm (size table).
• Ceramic body, silver-plated copper contacts.
• Standards printed: VDE 0636 Part 201, IEC 60269-1 and -2; dimensions according to DIN 43 620 parts 1 to 4.

Technical specification

Product data

Construction and size range

Selection and ordering guide

Pick aM when the circuit has a motor starting current that a gG fuse of the same continuous rating would not tolerate; the fuse can carry the motor start but must be paired with overload protection. For plain cable protection use gG (NH2GG50V400 on this site). Take the rating from the motor full-load current and the starting characteristics.

Other aM ratings in size 2 run from 35 A to 400 A; different catalog numbers apply.

Comparison from the datasheets: the aM 200 A fuse-link dissipates 11.3 W, whereas the gG 200 A fuse-link in the same size 2 body dissipates 18.5 W. The aM version also has a lower breaking capacity (80 kA versus 120 kA) and a higher voltage rating (690 V versus 500 V). These differences are why aM fuses are used on motor feeders and gG on cable feeders.

Installation and operation notes

Fit in a size 2 NH base or fuse switch; blown-fuse indication is by the double indicator. The datasheet notes that aM must be used with other protection against overload.

Replacement should be by qualified personnel with a fuse puller; the NH system cannot guarantee non-interchangeability of rated current.

Derived check: at 690 V three-phase, a 200 A circuit is about 239 kVA (square root of 3 x 690 V x 200 A); for a motor, the actual full-load current depends on power, efficiency and power factor and is normally below the fuse rating. The 200 A aM fuse-link can ride through motor starting currents, which is why the datasheet says its rated current can equal the motor nominal current.

Applications in Oman and the GCC

Pump, compressor, fan and crusher motor feeders on 400/690 V systems in oil and gas, mining, water and industrial plants, and in motor control centres where fuse plus contactor/overload relay combinations are used.

In hot environments follow the derating guidance of your motor-control assembly; the datasheet gives time-current curves.

Selection and handling notes

An aM fuse gives short-circuit protection only, so the motor circuit must also contain an overload relay or a motor protection device. Select the fuse from the motor starting current and the starting time, as the datasheet curves show how the fuse behaves under such overcurrents. Check that the 690 V rating matches the supply voltage and that the NH2 base is rated for the same voltage.

Information needed for a quotation

Send the full item code, the quantity, the delivery location in Oman or the GCC and any matching fuse bases, holders or handles, so that the complete protection package can be quoted together.

Documents and supply information

The manufacturer data sheet is attached to this page and should be read together with the project specification before a purchase is confirmed. Ratings, dimensions and protection classes are quoted as printed on that sheet. Lead time, stock position and certificates available with the shipment are confirmed in the quotation, and we supply to Oman and the wider GCC region for industrial, utility and building services projects.

Compatible accessories and related items

Related Mersen items on this site: gG fuses NH2GG50V400 and NH3GG50V630, semiconductor fuse NH1UD69V400PV, isolated-lug NH1GG50V200-1 and NH base BB01EP.

Frequently asked questions

What does aM mean?

A partial-range motor-protection characteristic: it breaks from 6.3 x In and gives short-circuit protection only; overload protection must come from other devices.

What are the ratings of NH2AM69V200?

Size 2, 200 A, 690 V ac, 80 kA ac, double indicator.

What is the item number?

V227971.

How much does it dissipate?

11.3 W at rated current.

Does Seven Star LLC act as a Mersen distributor?

No. Seven Star LLC is an independent supplier in Muscat that sources Mersen products on request.

Documents and quotation

This page carries the official Mersen datasheet for NH2AM69V200. Seven Star LLC is an independent supplier in Muscat and sources Mersen products on request; tell us the quantity and delivery point to receive a quotation. Always confirm the order code and technical values in the document first. See more in the product category.