Setec ST20-II User Manual

ST - II Series POWER SUPPLIES
USER INSTRUCTIONS
Introduction
These instructions detail the installation and operation requirements for the ST20-II & ST35-II
power supplies. These have been designed for operation in RV’s providing a DC power system,
with optional battery back up.
The units operate from 240Vac and provide an isolated 13.65Vdc output at 20A and 35A
respectively for powering the load and charging of batteries. All the necessary protection and
operating features for the load and batteries are provided. An optional DC input is also provided to
enable charging of batteries and powering of the load from an external +13.8V DC power source.
The units are fully enclosed ready for direct wall mounting. All connections are at the rear of unit
providing convenient wiring and installation. User access to all load and battery fusing has been
provided from the front of the unit.
Operation
Safety: Refer to the installation section before operating. Correct installation is the most critical
factor in ensuring the safe use of the power supply. If every consideration of these instructions has
been satisfied the power supply will be safe to operate.
Functional Diagram:
Figure 1 Functional Block Diagram
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AC Input
DC External
Input
Isense
5 x Load
Outputs
Battery
Output
Fuse Panel
AC / DC
Power Supply
Vadj
Battery Low Voltage
Disconnect circuit
0.8A
Trickle
+ve
-ve
+ve
-ve

Setec ST20-II Specifications

General

Model	ST20-II
Category	Power Supply
Input Frequency	50/60Hz
Operating Temperature	-10°C to +40°C
Protection	Over Voltage, Over Current, Short Circuit

Summary

Operation

Safety

Correct installation is the most critical factor in ensuring the safe use of the power supply.

AC/DC Power Supply

Provides isolated 13.65Vdc output for loads and float charging batteries.

Battery Features

Four-stage battery charging: Boost, Float, Store, Trickle for battery longevity.

Auxiliary Power Input

Alternative input for powering loads and charging batteries from a +12V system.

Protection and Fusing

Protection

Automatic protection for overload, short circuit, over-voltage, over-temperature, and reverse battery.

Fusing

Installation

Ventilation

Mechanical and Mounting

Wiring Up

Load, Battery, and DC Input Connections

Cabling Sizes

Battery Procedures

Battery Connection

Battery Disconnection

Batteries and Servicing

Battery Usage and Safety

Servicing and Fuse Replacement

Specifications

Battery Management

Charging Algorithm Description