
RLG 30 UNIT OVERVIEW
RLG 30 is a unit for automatically starting a diesel engine. It can be used for other internal
combustion engines as well.
It is designed to be easy to install and use, reliable, and provide at the same time the most
useful information to the end user without being confusing.
In the front part of the panel there are:
•
The AUTO – OFF – MANual selection switch.
•
A START button for manual start of the engine.
•
TEST button to check the condition of the batteries by making continuous start attempts.
•
Liquid Crystal Display with backlight so the information is visible at all times.
•
LED indicators for continuously refecting the unit's and the engine's state, so there is no
need to read the LCD all the time.
At the back of the panel there are:
•
Two dip-switches, one used to zero the internal hours-of-operation counter and the other to
enable or disable the DC preheat output.
•
A small trimmer potentiometer to adjust the activation time of the STOP output, used in
engines that stop with a choke device, an electromagnet that pulls to stop and then must
release.
•
A row of terminals for the connection of the engine's sensors and actuators.
•
A fuse, slow acting rated 3 amperes, or 4 amperes fast acting. This fuse protects internal
circuitry and the outputs: Fuel solenoid [9] (2,5 Α max), Alarm [13] (1 Α max). If greater current
is needed, an external relay should be used. Start output is protected by the external automatic
circuit breaker at the plus (+) terminal [5].
User adjustments are almost never needed. The unit chooses the best operating parameters
taking into account what is connected in its terminals. See Operation in Auto below.
The same unit is suitable for operation in 12V and 24V systems. All the inputs are active low
(when connected to battery minus), while the outputs are active high. When active, they source
+12 or +24 volts depending on the batteries. The inputs for the charger, the positive of the
battery and the D+ of the charging alternator, are analog and internally measured.
In terminals [20] and [21] an emergency stop switch -
N
ormally
C
losed- must be connected,
otherwise a bridge must be made there in order for the unit to operate at all.
OPERATION
The mode switch in OFF-RESET position
. The unit is not operational, it can not accept
Start command from the terminals or the manual START button in its panel. Only the Stop output
gets activated for the adjusted time and then stays deactivated as well. This position is used to
unlock the unit when it is stopped and locked by an error in the engine.
The mode switch in MAN position
. The user can start the engine by pressing the START
button. The starter is engaged for all the time the button is pressed. No DC preheat function is
available.
There is no error detection in this position. The engine does not stop automatically. To stop it,
the mode switch must go to OFF–RESET.
The mode switch in AUTO position
:
When the switch is frst put in this position, the display
lights up and shows some useful information. The unit does a voltage measurement to determine
the battery voltage it is connected to and adjusts accordingly the D+ level to be considered as
“engine running” voltage. The total hours that the engine has been operating is displayed. The
unit checks if the D+ [16] and the PSL [15] terminals are connected. If any of them is connected a
minus (-) return is present at its terminal. At least one of them must be connected for the unit to
be able to check engine running status. If none of these terminals provides signal, the unit does
not activate the starter. The unit checks frst for D+ connection, if it is connected, it is used. If D+
is not found, oil pressure [15] is used.
In idle state, the battery voltage is displayed and the charging current into it from the
connected charger in terminal [2].
Starting is commanded by bridging together by a closing contact terminals [10] and [11].