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SR/BR Multi-lamp LNER/BR Searchlight LMS Searchlight GWR Searchlight

Southern railway and british railways multi lamp colour light signal

SR style 4-aspect multi lamp colour light signal

The Southern Railway used colour light signals quite extensively starting in 1926 and these are the multi-lamp type that became the standard type used by Network Rail up until quite recently. They are the most widespread type of colour light signals to be found in the UK and can be two, three or four aspect and can have additional flashing aspects too.

3-aspect and 4-Aspect multi lamp signal operation table for CV38=1,CV38= 3, CV38=6, CV38=9 and CV38=14

Base state	Base+1 state	Aspect
Normal	Normal	Red
Reverse	Normal	Green
Normal	Reverse	Yellow
Reverse	Reverse	Double Yellow

* Note that three aspect signals will display single yellow in place of the double yellow indication

Multi lamp signal operation table for CV38=8

Base Red lamp	Base+1 Green lamp	Base+2 Yellow lamp*	Base+3 Yellow lamp**	Aspect
Reverse	Normal	Normal	Normal	Red
Normal	Reverse	Normal	Normal	Green
Normal	Normal	Reverse	Normal	Yellow
Normal	Normal	Reverse	Reverse	Double Yellow
Normal	Normal	Normal	Normal	Dark

* For 2-aspect signals Base+2 is the feather pivot lamp.
** For 2 and 3-aspect signals with a single feather Base+3 is the feather.
Flashing aspects can be displayed by toggling between the desired aspect and Dark

Multi lamp signal operation table for CV38=128, CV38=130 and CV38=133

Aspect number	Aspect display
0	Red
2	Green
1	Yellow
3	Double Yellow
4	Flashing Red
6	Flashing Green
5	Flashing Yellow
7	Flashing Double Yellow
8	Dark

* Note that not all signal types can display all of the aspects

Multi lamp signal wiring diagrams

2-aspect signal wiring

4-aspect signal wiring

Three or four aspect signal wiring diagram

2-aspect with feather wiring

Two aspect signal with feather and optional seperate pivot lamp wiring diagram

3-aspect with feather wiring

Three aspect signal with feather wiring diagram

4-aspect with multiple feathers wiring

Four aspect signal with feathers wiring diagram

Several CV38 settings are possible:-

CV38=8 - Any configuration (standard accessory protocol)
CV38=1 - 2x 4-aspect (standard accessory protocol)
CV38=3 - 1x 3-aspect or 4-aspect with multiple feathers (standard accessory protocol)
CV38=6 - 1x 3-aspect or 4-aspect with feather and 1x 2-aspect (standard accessory protocol)
CV38=9 - 2x 3-aspect with a feather (standard accessory protocol)
CV38=14 - 1x 3-aspect or 4-aspect 2x 2-aspect (standard accessory protocol)
CV38=129 - 4x 2-aspects (extended accessory protocol)
CV38=128 - 2x 4-aspects (extended accessory protocol)
CV38=130 - 2x 3-aspects with single feather (extended accessory protocol)
CV38=133 - 1x 3-aspect or 4-aspect with multiple feathers (extended accessory protocol)

If using JMRI with standard accessory protocol use the BR-2003 signal system with the signal head controlled mast driver.

For 2-aspect with CV38=8 use the 2-aspect signal mast with the double output signal head driver.
For 3-aspect with CV38=8 use the 3-aspect signal mast with the triple output signal head driver.
For 4-aspect with CV38=8 use the 4-aspect signal mast with individual lamps and use the single output signal head driver for each of the four lamps.
For 2-aspect with CV38=0 use the 2-aspect signal mast with the single output signal head driver.
For 3-aspect with CV38=1, 3, 6, 9 or 14 use the 3-aspect signal mast with the MERG signal head driver.

If using JMRI with extended accessory protocol use the BR-2003 signal system with the DCC signal mast decoder driver.

For 2-aspect with CV38=129 use the 2-aspect signal mast with the DCC Signal Mast Decoder driver
For 3-aspect with CV38=128, 130 or 133 use the 3-aspect signal mast with the DCC Signal Mast Decoder driver.
For 4-aspect with CV38=128 or CV38=133 use the 4-aspect signal mast with the DCC Signal |Mast Decoder driver.

Visit the JMRI BR-2003 signal system to see the available mast types.