6RA relays have a coil resistance of 76Ω, giving them a current draw of .16 amperes. The one 22RA relay I have tested has resistance of 16Ω, with a current draw of .75 amps. I don’t know why this is so. Do not use a 22RA relay in place of a 6RA unless you have checked the coil resistance.

Grey highlights in the following tables indicate that there is something odd about this particular relay and is probably a special purpose unit. I list 24v relays so you know not to use them.

I have listed all ICN SRB1xx, SRB2xx and SRB3xx here, even though many of the SRB3xx are ‘other’ devices such as external starter solenoids. Lucas now terms SRB100 to SRB303 as ‘Classic Relays’. SRB4xx and SRB5xx are ‘General Purpose Relays’ and are listed on the 26RA page. SRB3xx is the catchall for other things. SRB312 is a panel switch.

Notes
Note Number	Note	Illustration
1	XCB660a 1989 Cable Products
2	XCB630a 1993 Switchgear
3	XCB634 2006 Electrical Catalogue
4	PLM 5848 (Lucas Cable Products)
5	This is listed as a ‘starter relay’. Winding is 16 ohms (normal 77 Ω) Warning sticker says +VE feed to C2 IGN COIL to C4 Ebay vendor says used by Spitfire 77-80	TRF supersedes to LUSRB301
6	Lucas pub 400/71-72 CAV-Girling Equipment Specifications and Service Parts.
7	Heater Relay 76 XJS,75-76 XJ6also A/C relay, This unit has a special housing and pin out. It is listed here because the SRB303 would normally be a 6RA/22RA relay.
8	Winding is 16Ω. Comes with jumper between C1 and C4. Warning sticker says Important +VE feed to terminal C2. Ebay vendor lists this for Jaguar XJ-6, XJ-12 1974-1985 Door Lock Relay Jaguar XJ-6 1977-1985 Trunk Lock Relay Jaguar XJ-S 1985-1986 Door Lock Relay
9	Vendor said this is a Horn/Window relay for 1970-73 Stag. Has 4 contacts.
10	Vendor said this is for Bentley T & Continental 1966-73, RR Silver Shadow 1966-73. Has 5 contacts, no mounting bracket.
11	Pin-out & size information provided by Chris King
T	I have tested one and found this information to be correct.
ebay	Information from Ebay vendors. Chance of error may be somewhat higher than from Lucas catalogues
VII	Ebay listing from Vintage Imports Inc
EN	Engineering Number (old style part number)
ICN	International Catalogue Number (new style part number)
Cont	Rated for continuous use
Int	Rated for intermittent use
TRF	The Roadster Factory
p1	Contact C1 is double
p2	Contact C1 is single
p5	Change over relay. C3 is normally closed
p6	Double Contact. C1, C2 and C4 are normally open. C1,C2,C4 and W2 have double Lucar connectors.
p7	Double Contact. 33357 Has a jumper across C1 and C4; this is not illustrated.
cir1	Normally Open, C1 is double
cir2	Normally Open, C1 is single
cir3	Normally Closed
cir4	Change Over
cir6	Double Contact
cir7	Double contact supplied with external jumper connecting C1 to C4.
h1	Housing type 1
h2	Housing type 2
h3	Housing type 3 - no mounting bracket.

All images on this page copyright Lucas Electrical Ltd, 1989 unless otherwise noted.

6RA Relays
EN	ICN	Type	Amps	Volts	Duty	Desc	Pin out	Circuit	Housing	Notes
33213	SRB101	6RA		12v	Cont	Normally Open				4
33302b	SRB111	6RA	20a	12v		Normally Open	p1	cir1	h1	2
33311	SRB112	6RA							h2	VII,9
33316	SRB113	6RA	20a	12v		Normally Open	p2	cir2	h1	2,ebay
33209	SRB121	6RA		12v	Int	Normally Open	p1	cir1	h1	4,11
33223	SRB130	6RA		12v	Cont	Normally Closed				4
	SRB131	6RA	20a	12v		Normally Closed	p2	cir3	h1	2
33269	SRB142	6RA		12v 77Ω		Change Over	p5	cir4	h3	VII,10,T
	SRB143	6RA	20a	12v		Change Over	p5	cir4	h2	2
	SRB146	6RA	20a	12v		Change Over	p5	cir4	h1	2
	SRB201	6RA	10a	24v		Normally Open	p1	cir1	h1	2,4
33216	SRB210	6RA		24v	Int	Normally Open				4
	SRB220	6RA	10a	24v		Normally Closed	p2	cir3	h1	2
	SRB230	6RA	10a	24v		Change Over	p5	cir4	h1	2
	SRB301	6RA								3
33336		22RA								6
33356	SRB301	22RA		12v 16Ω		Double Contact	p6	cir6	h1	5
33357	SRB302	22RA		12v 18Ω		Double Contact		cir7	h1	ebay
33369	SRB303									7,ebay
33222		6RA		12v	Cont	Change Over				4
33231		6RA		12v	Cont	Normally Open Double Contacts				4