Shock Indicators Frequently Asked Questions

  • What is a shockmaster?
    Shockmaster is a low cost, compact mechanical device which may be installed on delicate equipment to monitor excessive shock and vibration, thereby assisting in the detection of hidden damage. When a container is opened, following shipment, there may appear to be no damage.

  • How do shockmasters work?
    The shockmaster consists of a spring-loaded weight with an integral trigger which engages with a spring-loaded sleeve, the entire assembly being enclosed in a metal housing with a transparent dome. When a shock occurs, the weight is forced down against its spring. If the shock is of sufficient magnitude, the trigger is disengaged from the sleeve, which, in turn, is forced by its own spring to move along a rod, exposing a red warning band.

  • How long will the shockmaster G-rating stay in tolerance?
    Since the springs in the shockmaster are never elongated, it will remain in tolerance indefinitely, provided it is not subjected to continuous motion of the moving parts and is not contaminated internally with foreign particles.

  • What is the shockmaster's area of response?
    The shockmaster has a hemispheric response: it indicates shocks from all directions radial to the unit, axial shocks to the base from beneath, and shocks from all directions between these planes. It will not register axial shocks applied to the dome from above. Models are also available with axial (base) response only. Two shockmasters are usually sufficient for even the largest of packaged items, and one may be adequate if there is no possibility of the equipment being shocked from above.

  • Is the shockmaster reusable?
    Yes. Shockmasters may be used over and over again. After tripping, the indicator is reset by removing the screw from the threaded hole in the side of the dome, inserting a stiff wire or straightened paper clip in the hole and pushing the black sleeve back to its cocked position. For shockmasters with ratings of 25 Gs or more, a plunger in the dome is depressed while the sleeve is pushed back as far as possible. The plunger is then released and the sleeve is allowed to return gently to its cocked position.

  • How accurate is the shockmaster?
    Standard Shockmasters trip within ±10% of their settings. On units set for 10 Gs or higher, tolerances of ±5% are available at an extra cost. They operate from -80°F to 160°F and are resistant to high humidity.

  • Is the shockmaster tamper-proof?
    Yes. To prevent tampering with the indicator after it has been tripped, a safety wire with an inspector’s seal attached can be placed through the resetting hole screws in the plastic dome. Or, inspector’s decals may be affixed over the reset holes. Shockmasters with ratings of 25 Gs or more are made tamper-proof by re-inserting one screw, threading safety wire through holes in plunger and screw head and securing with an inspector’s seal.

  • How can shockmaster help cut shipping and handling costs?
    In three ways: (1) shockmasters can be used to detect rough handling of a product on assembly lines or in other areas of your plant. Corrective measures may then be initiated to improve material handling procedures. (2) The shockmaster is an invaluable tool for shock tests to determine proper packaging design and materials. A row of indicators—each set for tripping at a different G-rating— may be used in container drop tests, thereby detecting both overpackaging and underpackaging of a product. (3) Terminal inspection time can be reduced substantially, as only those shipments with tripped indicators need be reinspected in detail.

  • How are shockmasters installed?
    Shockmasters may be mounted on the inside of the container or on the packaged item, depending on the information desired. There are four mounting holes in the base for rear mounting, or a mounting plate is available for front mounting of the units.

  • Can shockmasters be inspected without opening the container?
    Inspection may be accomplished by looking at the indicator through a hole with a removable cover in the container. Or, a shockmaster with electrical contacts may be used. This model can be inspected by placing the leads of an ohmmeter, or a battery and light bulb, on the contacts of a terminal board mounted on the outside of the container. If the Shockmaster is tripped, the ohmmeter will indicate that the circuit is closed, or the light bulb will glow.

  • What shockmaster settings are available?
    Shockmasters are available from stock in nominal ratings of 5, 10, 20, 25, 30, 35, 40 and 50 Gs. Other settings are available upon request. The standard equal-G models respond equally to shocks along the longitudinal axis and in the transverse plane. The standard long axis models respond to longitudinal axis shock only—side or transverse shocks have no effect.

  • Will your shock indicators prevent damage to my product?
    No. Our products only monitor shock impact.  However, one of the primary goals of using AGM’s shock impact indicator products is to build awareness of those individuals and companies handling your products.  The result should be better handling or better ability to prove mishandling; either way, the end result will be a reduction in damage to your products.