BS 6600-10:1985 download.Outline dimensions of transformers and inductors for use in telecommunication and electronic equipment Part 10: Specification for the outline dimensions of transformers and inductors using the Q range of C-cores.
1 Scope
This Part of BS 6600 specifies the overall and fixing centre dimensions of transformers and inductors, using the Q range of C-cores in accordance with BS 5347, for assembly forms C, H, J and U and also the screws to be supplied with them.
A preferred series of terminal positions together with their appropriate reference numbers is given in Appendix A for assembly forms C, H and J.
NOTE 1 Assembly forms C, H and J are well established and the reference letters used in earlier industrial and Ministry of Defence specificati3n8 (RCL 215 ard RCL 216. DFF 5214 and DEF STAN 59.37) have been retained.
NOTE 2 The titles of the publications referred to in BS 6600-10 are listed on the inside back cover.
2 Definitions
For the purposes of this Part of BS 6600 the following definitions apply.
2.1
form C assemblies
sealed assemblies of double loop C-cores mounted by tapped holes on the top or bottom faces with the magnetic axis horizontal
NOTE Terminals are commonly fixed in the top or bottom face of the assembly.
2.2
form H and form J asseniblies
assemblies of double ioop C-cores mounted by tapped holes on the top or bottom of the assembly with the magnetic axis horizontal
NOTE A terminal board forms an integral part of the assembly. In form J assemblies the reduced height is primarily achieved by having negligible clearance between the terminal board and the remainder of the assembly. This feature restricts the number of terminals which can be fitted and a form J assembly is therefore used for simpler windings such as chokes.
2.3
form U assemblies
assemblies of double loop C-cores mounted by clearance holes on four faces with the magnetic axis horizontal or vertical
NOTE No provision is made for terminals, but unused mounting holes may be used to fix a terminal board.
3 Dimensions
The dimensions of the various assembly forms using the Q range of C-cores shall be in accordance with Table 1, Table 2 and Table 3. All dimensions are in millimetres and include an allowance for a protective coating. The completed assembly shall be capable of accepting a gauge of the specified fixing centre dimensions and specified fixing hole size.
NOTE 1 Each assembly is given a unique code for reference purposes. This is of the form Qa.bZ where:
Q denotes the particular range of C-cores used in these
assemblies:
a is a number indicating a particular core within the Q range;
b refers to a strip width; and
Z is a letter which denotes the form of assembly used in
accordance with clause 1.
NOTE 2 The C dimensions given for forms H and J include a terminal board, but no allowance is made for the height of terminals as this will vary with application. The C dimensions for form C assemblies makes no allowance for the height of terminals.
No allowance has been made for terminals or terminal boards on form U as the use of these may increase dimensions. NOTE 3 In form U assemblies slotted fixing holes may be used to compensate for minor variations in assembly such as stack height.
NOTE 4 The purpose of Figure 1, Figure 2 and Figure 3 is to provide a guide to the appearance of the completed assembly and references for the corresponding tables of dimensions. They are not intended to specify details of the piece parts.
NOTE 5 The tables give figures for the approximate mass of complete assemblies. These figures are based on a full bobbin of copper wire and a silicon-iron core.
4 Fixing screws and washers
Assembly forms C, H and J shall be supplied with ISO metric, hexagon headed steel fixing screws of diameter and length as given in Table 1 and Table 2, such screws being in accordance with BS 3692. Four screws with assemblies Q5. I C to Q9.4C and eight screws with assemblies Q1O.1C to Q11.2C shall be supplied.
The screw threads shall be metric coarse, medium fit M4 X O.7-6g, M5 X O.8-6g, M6 X 1.O-6g or MS x 1.25-6g as appropriate, in accordance with BS 3643.
The associated tapped holes shall be at least as deep as the length of the screw and shall comply with a 6H class of fit.
Each screw shall be supplied with an appropriately sized steel tab washer which complies with BS 5814. The finish on screws and washers shall be in accordance with BS 3382-1.