The IK and IP of enclosures
Original article date: February 1998
The IP ratings for enclosures are well documented. But what is the IK Code for mechanical impact? Alan Quinn went to find out.
The IP Code defined in the standard BS EN 60529:1992 degrees of protection provided by enclosures (IP Code) provides a means of specifying the ability of an enclosure to protect its contents from external objects. The standard applies to enclosures for electrical equipment with a rated voltage not exceeding 72.5kV.
Perhaps less well known is the IK Code, which deals with mechanical impacts. It is defined in the standard BS EN 50102: 1995 Degrees of protection provided by enclosures for electrical equipment against external mechanical impacts (IK Code). It provides a means of specifying the capacity of an enclosure to protect its contents from external impacts.
Before the advent of EN 50102, a third numeral used to be added to the IP Code to indicate the level of impact protection – eg IP66(9). Non-standard use of this system was one of the factors leading to the development of the standard, which uses a separate two numeral code to distinguish it from the old differing systems. The standard came into effect in October 1991 and conflicting standards were supposed to have been withdrawn by April of last year.
EN 50102 specifies the way enclosures should be mounted when tests are carried out, the atmospheric conditions that should prevail, the number of impacts (5) and their (even) distribution, as well as the size, style, material and dimensions of the various types of hammer, designed to produce the energy levels required.
* GAMBICA, the association for the instrumentation, control and automation industry in the UK, has published a new colour handbook as a guide to specifiers and users of enclosures for electrical and electronic systems. The handbook covers every aspect of application, materials, standards, ratings and safety. It also details environmental considerations and hazardous areas. A useful list of enclosure suppliers and their individual services is also included.
Table 1: IK Code and impact energy
| IK Code | IK00 | IK01 | IK02 | IK03 | IK04 | IK05 | IK06 | IK07 | IK0 8 | IK09 | IK10 |
| Impact Energy | * | 0.15 | 0.2 | 0.33 | 0.7 | 1 | 2 | 5 | 10< /td> | 20 |
Table 2 Impact test characteristics
| IK Code | IK00 | IK01 to IK05 | IK06 | IK07 | IK08 | IK09 | IK10 |
| Impact Energy (J) | * | <1 | 1 | 2 | 5 | 10 | 20 |
| R (mm) | * | 10 | 10 | 25 | 25 | 50 | 50 |
| Material | * | polyamide | polyamide | steel | steel | steel | steel |
| Mass (kg) | * | 0.2 | 0.5 | 0.5 | 1 .7 | 5 | 5 |
| Pendulum hammer | * | YES | YES | YES | YES | YES | YES |
| Spring hammer | * | YES | YES | YES | NO | NO | NO |
| Free fall hammer | * | NO | NO | YES | Y ES | YES | YES |
Note: R is the radius of the striking element
February 1998