Section 1 — General Information
“HS” Type Transfer Switch
1.1INTRODUCTION
This manual has been prepared especially for the purpose of familiarizing personnel with the design, application, installation, operation and servicing of the applicable equipment. Read the manual carefully and comply with all instructions. This will help to prevent accidents or damage to equipment that might otherwise be caused by carelessness, incorrect appli- cation, or improper procedures.
Every effort has been expended to make sure that the contents of this manual are both accurate and cur- rent. The manufacturer, however, reserves the right to change, alter or otherwise improve the product at any time without prior notice.
1.2EQUIPMENT DESCRIPTION
The automatic transfer switch is used for transfer- ring electrical load from a UTILITY (NORMAL) power source to a EMERGENCY ( STANDBY) power source. Such a transfer of electrical loads occurs automati- cally when the UTILITY power source has failed or is substantially reduced and the EMERGENCY source voltage and frequency have reached an acceptable level. The transfer switch prevents electrical feedback between two different power sources (such as the UTILITY and EMERGENCY sources) and, for that reason, codes require it in all standby electric system installations.
The transfer switch consists of a transfer mechanism, a relay control, and a terminal strip for connection of sensing wires.
This switch is suitable for control of motors, electric discharge lamps, tungsten filament and electric heat- ing equipment and the tungsten load does the switch rating.
The transfer switch is for use in optional standby systems only.
The transfer switch is suitable for use on a circuit capable of 10,000 rms symmetrical amperes, 240 VAC when protected by a circuit breaker without an adjustable short time response or by fuses.
1.3TRANSFER SWITCH DATA DECAL
A DATA DECAL is permanently affixed to the transfer switch enclosure. Use this transfer switch only with the specific limits shown on the DATA DECAL and on other decals and labels that may be affixed to the switch. This will prevent damage to equipment and property.
When requesting information or ordering parts for this equipment, make sure to include all information from the DATA DECAL.
Record the Model and Serial numbers in the space provided below for future reference.
MODEL #
SERIAL #
1.4TRANSFER SWITCH ENCLOSURE
The standard switch enclosure is a National Electrical Manufacturer’s Association (NEMA) 3R type. NEMA 3R type enclosures primarily provide a degree of pro- tection against falling rain and sleet and is not dam- aged by the formation of ice on the enclosure.
1.5SAFE USE OF TRANSFER SWITCH
Before installing, operating or servicing this equip- ment, read the SAFETY RULES (inside front cover) carefully. Comply strictly with all SAFETY RULES to prevent accidents and/or damage to the equipment. The manufacturer recommends that a copy of the SAFETY RULES are posted near the transfer switch. Also, be sure to read all instructions and information found on tags, labels and decals affixed to the equip- ment.
Two publications that outline the safe use of transfer switches are the following:
•NFPA 70; National Electrical Code
•UL 1008, STANDARD FOR
2
