2.2 Utility Power Connection
CAUTION: The “Utility Power Connection” procedure must ONLY be performed by qualified
service personnel and in compliance with local electrical codes and common safety
practices. Connection to utility power must be approved by the local utility before
installing the power supply.
NOTE: UL and NEC require that a service disconnect switch (UL listed) be provided by the
installer and be connected between the power source and the ALPHA power supply.
Connection to the power supply must include an appropriate service entrance weather
head.
Wiring the Utility Service
NOTE: A “high-magnetic” trip circuit breaker must be used in order to accommodate the
high-inrush currents normally associated with the start-up of ferroresonant
transformers (400 Amp, no-trip, first half cycle). Do not replace this circuit breaker
with a conventional service entrance circuit breaker. Alpha recommends Square D
circuit breakers ONLY, because of increased reliability in this powering application.
Alpha Technologies offers a high-magnetic Square D circuit breaker and a BBX option (a UL Listed
service entrance). Contact your local sales representative for more information.
In most cases, the following configurations (see next page) qualify for service
entrance use, however, other codes may apply. Always contact your local utility to
verify that the wiring conforms to applicable codes.
11 031-106-C1-001 Rev. A
2. Installation
Description
240V Installation — HACR (15A)
120V Installation — High-magnetic (20A)
120V Installation — High-Magnetic (15A)
BBX — External Service Disconnect
Alpha Part Number Square D Part Number
470-224-10
470-017-10
470-013-10
020-085-10
QO215
QO120HM
QO115HM
QO2-4L70RB
470-017-10
QO8-16L100RBBBX — External Service Disconnect 020-141-10
Table 2-1 Service Entrance Circuit Breaker Requirements
