Holiday Trip 2012, Owner'S Manual

Page: 178 / 242

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2012 Trip
Battery maIntaIner
The Battery
Maintainer
(Bi-Directional
Isolator Relay
Delay) constantly
senses voltage
of the house and
chassis batteries.
With engine
running, both the house and chassis batteries
are charged from the engine alternator. When
the motorhome is plugged into shore power or
operating from the generator, both the house
and chassis batteries are charged from the
inverter. 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.
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. Located on
the side of the relay is a schematic identifying
the relay as a Number 87 or 87A. The two
relay types differ in function and if mixed, will
create problems.
Ensure the replacement relay is of the
same type and current rating to assure proper
operation.
Relay Post Identification:
1. The 30 post is generally the supply
from a fuse or circuit. Some
applications use the 30 post for
ground. The 30 post can be used
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 on a Number 87 relay
are not common to the 30 post until
the relay coil is tripped.
5. The 87A posts on a Number 87A
relay, are common to the 30 post at
rest (Normally Closed). When the
coil is tripped, the 87a post becomes
inactive and the 30 post becomes
common with the 87 post.
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.
NOTE:
When there is power applied to the
coil, the coil sets up a magnetic field
in the windings. When the power
is removed, the field collapses. A
momentary high voltage discharge
will occur. This is how an ignition coil
works.
090518b
Located in front
distribution panel
080406
080405b
080405c
080405d
Single Pole Single Throw Relay.
080405