Phase out / discontinued check availability – Computronic Controls Sentinel 70 User Manual
Page 5

CCL – Sentinel 70/140 installation and operation ci0012 issue 3 6
th
May 2011 p5/6
General
Electrical connection is via screw terminal blocks on the 
Sentinel circuit board. 
For SNS models:-
For SNL models:-
On enclosed ESNS/ESNL models, an additional terminal 
block provides convenient connection of AC supply and 
DC output. The AC supply Earth must be connected to the 
stud connector on the metal enclosure, as shown below. 
For ESNL models:-
DC Output
Before DC connection or disconnection:- 
 Ensure AC supply input is isolated. 
Disconnecting the batteries while the 
AC supply is live can result in sparking at 
the battery terminals, ignition of battery 
gasses and serious personal injury. 
 Check that the charger output is compatible
with battery type & voltage. Incompatibility 
may result in damage to the charger, 
batteries and serious personal injury. 
Connect the Sentinel output to the battery terminals, 
observing the warnings above and the correct DC polarity. 
The Sentinel output includes a self-resetting polyfuse 
for protection of reverse polarity and short-circuit faults. 
In the event of such faults, isolate the AC supply, 
disconnect the output terminals and allow the fuse to reset; 
replacement of the fuse should not be necessary. The 
charger can then be re-connected and switched back on. If 
the fuse fails to reset, return the charger to the supplier. 
Auto Boost Initiate
On (E)SNL chargers, two terminals may be linked 
(e.g. using an operator-controlled momentary push button 
or panel switch) to give manual initiation of an Auto Boost 
cycle (at any time, regardless of battery voltage). 
Alarm output
All Sentinel models include a relay-based output for 
remote signalling of faults. During fault conditions, the 
relay de-energises and the output gives a negative DC 
signal, rating 1A max. at 30 VDC. 
(E)SNS models monitor charge fail faults, i.e. AC supply or 
fuse failure, DC fuse failure or low/zero current output. 
(E)SNL models monitor for charge fail faults, plus battery 
low voltage and battery high voltage. 
The alarm relay de-energises immediately on detection of 
a charge fail fault, and 120 sec after detection of low or 
high battery voltage faults (to allow for normal voltage 
variations, e.g. during engine cranking). 
AC Input (power supply)
Before AC connection, disconnection or fuse 
replacement:- 
 Isolate the AC supply 
 Ensure a good earth connection to the earth 
stud on the charger’s metal chassis.
 Ensure the AC supply voltage is compatible
with the charger’s supply rating. Exceeding 
the rated voltage may result in damage 
to the charger and connected equipment, 
and cause serious personal injury. 
All Sentinel models are fitted with mains AC input fuses, 
with ratings as labelled on each charger.
ELECTRICAL CONNECTION
DANGER !
HIGH VOLTS
WARNING: DANGER OF INJURY OR DEATH. During normal operation, Sentinel is 
connected to high voltage AC circuits. Before connection, disconnection or handling of 
these chargers, ensure isolation of all AC power supplies. Connection or disconnection 
with live wiring can also cause hazardous sparking and component damage. 
PHASE
OUT
/ DISCONTINUED
Check
Availability
