Relays - Holiday Navigator 2003 Owner's Manual

The coach uses different relays to operate different equipment. If a relay
needs to be replaced, carefully record the location of each wire and its color.
The relays may look the same but they are completely different. Look at
the side of the relay to determine whether you need an 87 relay or an 87a
relay. These relays can be easily mixed and the problem may increase if the
wrong one is changed. These two relays can be wired many different ways to
operate different functions. Turn the relay over and look at the post. Each post
is numbered. It is important to note these differences listed:
1. The 30 post is the incoming fuse and/or breaker power. Some
relay applications supply power to the 30 post. Some use it for
ground. The 30 post can be used many different ways.
2. The 85 post is one side of the coil, tripped different ways.
3. The 86 post is the opposite side of the coil, tripped different ways.
4. The 87 posts are not common to the 30 post until the relay is
tripped. When the relay trips, both 87 posts are common to the
30 post.
5. Using an 87a relay, the 30 post and the 87a post are common.
When the coil is tripped, the 87a becomes a dead post and then
the 30 post becomes common to the 87 post located on the outside
of the relay.
Bosch Relay.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
30
87
86
30
87 Relay.
N A V I G A T O R 2 0 0 3
30
85
87a
86
87
87a Relay.
Electrical Systems - Chassis
85
87
9 • 3 4 7

Relays