BS 7797:1998

Committees responsible
Foreword
Specification
1 Scope
2 References
3 Definitions
4 Heating elements
5 Rating
6 Degree of protection
7 Electrical insulation
8 Thermal insulation
9 Construction
10 Supply connections
11 Terminations for external conductors
12 Provision for earthing
13 Internal wiring
14 Mounting of components
15 Screws and connections
16 Creepage distances, clearances, and distances through
    insulation
17 Controls
18 Labels and warning notices
19 Routine testing
20 Instructions
21 Marking
Annexes
A (normative) methods of test
B (informative) Guidance for installation and maintenance
    of duct heaters
Tables
1 Power output
2 Minimum thickness of metallic enclosures
3 Terminal sizes
4 Fastening strength of terminals
5 Dimensions of pillar terminals
6 Dimensions of screw terminals
7 Dimensions of stud terminals
8 Minimum spacings
9 Creepage distance and clearances
10 Temperature marking for supply connections
11 Symbols for marking
    A.1 Torque values for screw torque test
    A.2 Torque values for screw torque test, for terminals
          described in 11.2.3 and 11.3.3
List of references

Defines requirements for industrial electric heaters having a rated voltage to 440 V, which use metal-sheathed elements and are installed in a duct run, for heating in forced air systems or heating of non-flammable gases, when the heaters have fixed, replaceable or removable elements.

This British Standard specifies requirements for industrial electric heaters with a rated voltage of up to 440 V, using metal-sheathed elements and installed in a duct run, for heating in forced air systems or for heating of non-flammable gases.

The heaters may have fixed, replaceable or removable elements.