EN 61439-2: Power switchgear and controlgear assemblies

5 - Interface Characteristics

Last update 09/04/2020

In chapter 5 the interface characteristics are listed. In particular, the assembly shall ensure compatibility with the rating of the circuits to which it is connected and the installation condition and shall be declared by the assembly manufacturer. The assembly manufacturer shall give the following values: 

-    Voltage ratings

  • Rated voltage U(highest nominal voltage of the electrical system, a.c. (r.m.s.) or d.c., declared by the assembly manufacturer, to which the main circuit(s) of the assembly is (are) designed to be connected § 3.8.9.1)
  • Rated operational voltage U(value of voltage, declared by the assembly manufacturer, which combined with the rated current determines its application § 3.8.9.2)
  • Rated insulation voltage U(r.m.s. withstand value, assigned by the assembly manufacturer to the equipment or to a part of it, characterising the specified (long-term) withstand capability of the insulation § 3.8.9.3)
  • Rated impulse withstand voltage Uimp (impulse withstand voltage value, declared by the assembly manufacturer, characterising the specified withstand capability of the insulation against transient overvoltages § 3.8.9.4) 

-    Current Ratings

  • Rated current of the assembly Ina
  • Rated current of a circuit Inc
  • Rated peak withstand current Ipk (value of peak short-circuit current, declared by the assembly manufacturer, that can be withstood under specified conditions § 3.8.10.2)
  • Rated short-time withstand current Icw (r.m.s value of short-time current, declared by the assembly manufacturer, that can be withstood under specified conditions, defined in terms of a current and time § 3.8.10.3)
  • Rated conditional short-circuit current of an assembly Icc (value of prospective short-circuit current, declared by the assembly manufacturer, that can be withstood for the total operating time of the short-circuit protective device (SPCD) under specified conditions § 3.8.10.4)

-    Rated diversity factor RDF (per unit value of the rated current, assigned by the assembly manufacturer, to which outgoing circuits of an assembly can be continuously and simultaneously loaded taking into account the mutual thermnal influences § 3.8.11)

-    Rated frequency f(value of frequency, declared by the assemblu manufacturer, for which a circuit is designed and to which the operating conditions refer § 3.8.12)

In addition, the assembly manufacturer shall declare the following characteristics: 

a)    Additional requirements depending on the specific service conditions of a functional unit; 
b)    Pollution degree (which could be 1, 2, 3 or 4); 
c)    Types of system earthing for which the assembly is designed (TT or TN); 
d)    Indoor and/or outdoor installation;
e)    Stationary or movable;
f)    Degree of protection; 
g)    Intended for use by skilled or ordinary persons; 
h)    Electromagnetic compatibility (EMC) classification (Environment A or Environment B); 
i)    Special service conditions, if applicable; 
j)    External design (open-type assembly; enclosed assembly; desk-type assembly; box-type assembly..etc);
k)    Mechanical impact protection, if applicable; 
l)    The type of construction – fixed or removable parts; 
m)   The nature of short-circuit protective device(s); 
n)    Measures for protection against electric shock; 
o)    Overall dimensions, if required; 
p)    The weight, if required.
 

Safety in Collaborative Robotics

There is no “Collaborative Robot”. That is one of the first statements you hear from people working in Collaborative Robotics. The reason is because the robot can be designed for a collaborative task, but it is the Application that makes the “Robot Collaborative”. The reference standard for Collabo