General; Standards And Specifications; Operating Conditions; Normal Operating Conditions - ABB UniGear ZS1 Instruction Manual

1. Summary

1.1 General

1.2 Standards and specifications

1.3 Operating conditions

UniGear is the new name of the ZS1 switchgear in release 1.2 (ZS1.2). It is three-phase, metal-clad,
air insulated switchgear and all the units are factory-assembled, type-tested and suitable for indoor
applications up to 24 kV.
The units are designed as withdrawable modules and are fitted with a single busbar system. The
withdrawable parts are equipped with circuit-breakers and contactors.
Details of the technical design and configuration of individual switchgear, such as the technical data,
detailed equipment lists for the individual panels and comprehensive circuit documentation etc., can
be found in the relevant order documents.
Note
The UniGear ZS1 switchgear is indicated in the test reports and type test certificates with the
abbreviation ZS1.2
UniGear ZS1 switchgear panels comply with the standards and specifications for factory-assembled,
metal-enclosed and type tested high voltage switchgear to IEC publications 62271-200 and 60694. In
addition, in accordance with IEC 60529, the switchgear panels have the following degrees of
protection: IP4X for the enclosure and IP2X for the partitions.
All other corresponding IEC publications, national or local safety at work regulations and safety
regulations for production materials must be followed during erection and operation of these systems.
Above and beyond this, the order-related data from ABB must be taken into account.

1.3.1 Normal operating conditions

The switchgear are basically suitable for normal operating conditions for indoor switchgear and
switchboards in accordance with IEC 60694. The following limit values, among others, apply:
Ambient temperature:
Maximum
Maximum 24 h average
Minimum (according to "minus 5 indoor class")
The maximum site altitude is 1000 m above sea level.

1.3.2 Special operating conditions

The switchgear are suitable for operation in the climate of Wda type according to IEC 60 721-2-1.
Special operating conditions must be discussed with the manufacturer in advance. For example:
• At site altitudes above 1000 m, the effects of the reduction in dielectric strength of the air on the
insulation level must be taken into account (please refer to diagram in figure 1/1).
• Increased ambient temperatures must be compensated for in the design of the busbars and branch
conductors as well as for the withdrawable parts, otherwise the current carrying capacity will be
limited. Heat dissipation in the switchgear panel can be assisted by fitting additional ventilation
facilities.
Note on any special climatic operating conditions
When switchgear are operated in areas with high humidity and/or major rapid temperature fluctua-
tions, there is a risk of dew deposits which must remain an exception in normal operating conditions
for indoor switchgear. Preventive action (e.g. fitting electric heaters) must be taken in consultation with
the manufacturer to avoid this condensation phenomenon and any resulting corrosion or other adverse
effects. The control of the heaters depends on the relevant project and details must be taken from the
order documents.
Figure 1: Curve for determination of the altitude factor k in relation to the altitude H.
+40 °C
+35 °C
-5 °C
3