Holiday 2011 Aluma Lite, Owner'S Manual

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9
BATTERY MAINTAINER
The BIRD (Bi-Directional Isolator Relay
Delay) constantly senses voltage of the house
and chassis batteries.
With engine running, the alternator on the
engine will maintain chassis and house battery
voltage. When the motorhome is plugged
into shore power or operating from the
generator, both the house and chassis batteries
are charged from the converter. If neither
battery is being charged, the batteries are fully
isolated.
The battery maintainer also senses heavy
loads on either battery to prevent the wrong
battery from being inadvertently discharged.
The bi-directional isolator relay is a circuit
board found on the front distribution panel.
Relays
The motorhome uses various
relays to operate electrical
equipment, such as lights and
motors. If a relay needs to be
replaced, carefully record the
location of each wire and all
markings or labels.
Relays can look the same in appearance but
differ in function. Note that on the side of the
relay is a schematic drawing identifying if the
relay is 87 or 87a relay. These current ratings
differ, and if mixed, will create problems.
Ensure the replacement relay is of the current
rating to assure proper operation.
Another indicator to the type of relay is the
post or legs. Turn the relay over and look at
the post.
Note the differences between the numbered
posts:
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 post becomes
inactive and the 30 post becomes
common to the 87 post located on the
outside of the relay.
A Single Pole Single Throw relay (SPST) is
an electro-magnetic switch consisting of a coil
(terminals 85 & 86), one common terminal
(30), one normally closed terminal (87a), and
one normally open terminal (87).
When the coil of the relay is at rest (not
energized) the common terminal (30) and
the normally closed terminal (87a) have
continuity. When the coil is energized, the
common terminal (30) and the normally open
terminal (87) have continuity.
080406
080405b
080405c
Located on front distribution panel
090158b
080405d
Single Pole Single Throw Relay