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Instructional Booklet
Page 2Effective: June 2007 Instruction Manual for the Eaton RTC-50
Automatic Transfer Switch Controller
SECTION 1: INTRODUCTION1.1 Preliminary Comments and Safety Precautions
This technical document is intended to cover all aspects associ-
ated with the installation, application, operation, and maintenance
of the Automatic Transfer Switch Controller (RTC-50). It is pro-
vided as a guide for authorized and qualified personnel only in the
selection and application of the RTC-50 controller. Please refer to
the specific WARNING and CAUTION in Section 1.1.2 before pro-
ceeding. If further information is required by the purchaser regard-
ing a particular installation, application, or maintenance activity,
please contact an authorized Eaton Electrical Sales Representative
or the installing contractor.
1.1.1 Warranty and Liability Information
No warranties, expressed or implied, including warranties of fit-
ness for a particular purpose of merchantability, or warranties aris-
ing from course of dealing or usage of trade, are made regarding
the information, recommendations and descriptions contained
herein. In no event will Eaton be responsible to the purchaser or
user in contract, in tort (including negligence), strict liability or
otherwise for any special, indirect, incidental or consequential
damage or loss whatsoever, including but not limited to damage or
loss of use of equipment, plant or power system, cost of capital,
loss of power, additional expenses in the use of existing power
facilities, or claims against the purchaser or user by its customers
resulting from the use of the information and descriptions con-
tained herein.
1.1.2 Safety Precautions
All safety codes, safety standards, and/or regulations must be
strictly observed in the installation, operation, and maintenance of
this device.
1.2 General Information
Automatic Transfer Switches (ATS) are used to protect critical
electrical loads against loss of power. The load’s Utility power
source is backed up by an alternate power source such as a Gen-
erator. An ATS is connected to both the Utility and Generator
power sources and supplies the load with power from one of the
two sources. In the event that power is lost from Utility, the ATS
transfers the load to the Generator power source. Once Utility
power is restored, the load is automatically transferred back to the
Utility power source.
An intelligence system initiates the transfer when the Utility
power fails or falls below a preset voltage. An engine start is then
initiated by the Generator and the ATS transfers to the Generator
power source when sufficient Generator voltage is available.
When the Utility power is restored, the ATS automatically trans-
fers back to the Utility and the Generator will shut down after a
time delay.
ATSs automatically perform the transfer function, and include
three basic elements:
1. Main contacts to connect and disconnect the load to and from
the power sources.
2. Solenoids to make the transfer of the main contacts from
source to source.
3. Intelligence/supervisory circuits to constantly monitor the con-
dition of the power sources and thus provide the intelligence
necessary for the switch and related circuit operation.
This manual deals with the third basic element of the ATS, the
required intelligence/supervisory circuits. The RTC-50 controller
advances the application of intelligence, supervisory, and pro-
gramming capabilities for ATS equipment.
1.3 Product Overview
The RTC-50 controller is a comprehensive, multi-function, micro-
processor-based ATS controller. Designed to meet the needs of
markets worldwide, the RTC-50 controller:
•Is a UL Listed Component
•Complies with UL 1008/ CSA 22.2-178
•Complies with UL 991 environmental tests
•Complies with IEC 61000-4-2, 61000-4-3, 61000-4-4, 61000-
4-5, 61000-4-6, and 61000-4-11
•Complies with CISPR 11, Class B
•Complies with FCC Part 15, Class B
•Meets European Standards Conformance (CE mark)
The RTC-50 controller provides an unmatched degree of pro-
grammed flexibility to address the needs of any system. It oper-
ates on 240 VAC, single-phase at 50 or 60 Hz. The RTC-50
controller monitors the condition of the line voltage of both the
Utility and Generator power sources. The RTC-50 controller pro-
vides the necessary intelligence to insure that the transfer switch
operates properly through a series of programmed sensing and
timing functions.
CAUTION
ALL POSSIBLE CONTINGENCIES THAT MAY ARISE DURING INSTAL-
LATION, OPERATION, OR MAINTENANCE, AND ALL DETAILS AND
VARIATIONS OF THIS EQUIPMENT DO NO PURPORT TO BE COV-
ERED BY THESE INSTRUCTIONS. IF FURTHER INFORMATION IS
DESIRED BY THE PURCHASER REGARDING A PARTICULAR INSTAL-
LATION, OPERATION, OR MAINTENANCE OF PARTICULAR EQUIP-
MENT, PLEASE CONTACT AN AUTHORIZED EATON ELECTRICAL
SALES REPRESENTATIVE OR THE INSTALLING CONTRACTOR.
WARNING
THE WARNINGS AND CAUTIONS INCLUDED AS PART OF THE PRO-
CEDURAL STEPS IN THIS DOCUMENT ARE FOR PERSONNEL SAFETY
AND PROTECTION OF EQUIPMENT FROM DAMAGE. AN EXAMPLE
OF A TYPICAL WARNING LABEL HEADING IS SHOWN ABOVE TO
FAMILIARIZE PERSONNEL WITH THE STYLE OF PRESENTATION.
THIS WILL HELP TO INSURE THAT PERSONNEL ARE ALERT TO
WARNINGS, WHICH APPEAR THROUGHOUT THE DOCUMENT. IN
ADDITION, WARNINGS AND CAUTIONS ARE ALL UPPER CASE AND
BOLDFACE.
WARNING
COMPLETELY READ AND UNDERSTAND THE MATERIAL PRESENTED
IN THIS DOCUMENT BEFORE ATTEMPTING INSTALLATION, OPERA-
TION, OR APPLICATION OF THE EQUIPMENT. IN ADDITION, ONLY
QUALIFIED PERSONS SHOULD BE PERMITTED TO PERFORM ANY
WORK ASSOCIATED WITH THI S EQUIPMENT. ANY WIRING
INSTRUCTIONS PRESENTED IN THIS DOCUMENT MUST BE FOL-
LOWED PRECISELY. FAILURE TO DO SO COULD CAUSE PERMA-
NENT EQUIPMENT DAMAGE.