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OD Enclosure Seismic & Overhead Lifting Analysis

With great anticipation DDB is proud to announce the complete line of OD Enclosures are now tested to Zone 4 Seismic Compliance.  All 4 families (OD, WOD, 2OD & 3OD) have now been tested to meet and exceed the Telcordia GR 63 standard.  Zone 4 Seismic asks for less than 3” of deformation of the enclosure and aging the OD family over performed with less than 1/2” deformation.  When properly loaded and anchored the OD family exceeds the safety standards set forth by ASME B30.20, B30.9 and placed for seismic compliance. The “elastic stress analysis method” is also used to satisfy all the seismic design by analysis requirements set forth by Telcordia GR 63.

But we didn’t stop at the Zone 4 seismic testing. In addition to being extremely functional and feature rich the entire OD family (OD, WOD, 2OD & 3OD) has also been tested to overhead lifting standards with incredibly high scores in overhead lifting.

To our existing customers these achievements come as little surprise due to our rugged construction and continued dedication to American quality; all backed by an industry leading 15-year warranty.

OD Enclosure Seismic & Lifting Analysis (PDF)

Wind Load Analysis Study

Executive Summary On December 1, 2011, SolidBox published a report regarding a series of structural analyses that were conducted on the OD, 2OD, & 3OD (Outdoor) enclosures to verify their integrity in high-wind conditions, specifically winds up to 150MPH.

Since the publication of the original report, the ASCE has updated its Basic Wind Speeds charts to reflect increases in overall wind speed. The peak design wind speeds have increased from 150MPH to 181MPH, per ASCE 7-10. As a result, DDB contracted SolidBox to reanalyze its enclosures for these higher wind speeds. Initial findings of the analysis showed loads and stresses near the conservative, self-imposed, limits requested by DDB. SolidBox suggest slight modifications to the Alumashield brackets, rivets, and mounting hardware. DDB created an upgrade option to the Alumashield cover specifically for locations where the peak sustained wind speed can exceed 150MPH. This report details the steps taken to verify compliance of the upgraded Alumashield cover.

This analysis proves that the upgraded Alumashield covers for the OD, 2OD, & 3OD enclosures are safe for operation in winds up to 200MPH.

Wind Load Analysis Study (PDF)

Moisture and/or Condensation is a Major Concern

Moisture and/or condensation is a major concern to any outdoor enclosure. Typically condensation and the chemicals that adhere to the condensation are a major cause of system faults in electronics equipment.

The key to keeping moisture from forming in an outdoor cabinet is to insure that the cabinet inside temperate is above the dew point. As the humidity outside of the cabinet is at or above RH 80 % and ambient temperature are above 80 degrees F the separation between the dew point and the cabinet inside temperature become very close about 5 to 7 degrees F.

Temperature and Condensation (PDF)

Things to Consider When Choosing an Enclosure for an OSP Application

Selecting the right enclosure for an outdoor application for the first time can be a daunting task and should be addressed with a systematic approach in order to minimize problems in the field. Once the enclosure has been placed in the field the number of options becomes limited and often expensive to correct. This document is intended to provide a check list up front for the initial design to eliminate as many issues prior to installation as possible.

Things to Consider When Choosing an Enclosure for an OSP Application (PDF)

Remember that NEMA-4 is dust tight but not air sealed and moisture is a gas contained within the air and will eventually penetrate the cabinet.

With direct air cooled cabinets the recommended temperature range is 90 to 104 degrees F to prevent condensation from forming. Air conditioned cabinets are a different story since the evaporator coil in the air conditioner will remove the moisture in the cabinet due to the temperature of the evaporator coil being below the dew point. This condensation is then routed outside of the cabinet via a drain tube.

Preventing Condensation (PDF)

Call and let our experienced team help you with your build.