Siemens 3PCI Series, Operation Manual

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3PCI SCR Power Controller Series Manual Introduction
Version 1.2 (19000325)
s
1-1
CHAPTER 1: INTRODUCTION
In This Section:
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Overview ..............................................................1-1
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Operation .............................................................1-2
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Three-phase Overcurrent (OC) Trip Feature.......1-2
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Three-phase Current Limit (CL) Feature .............1-2
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Options.................................................................1-3
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Technical Specifications ......................................1-3
1.1. Overview
This manual covers the 3PCI (3-phase, cosine intercept) series of power controllers by
s LD R
. The
3PCI models are rated from 25 A through 1200 A (as specified in Table 1-2 on page 1-5). Series 3PCI power
controllers provide control of three-phase power to resistive and inductive loads. The 3PCI utilizes infinite
firing angle resolution for precise SCR control. A typical 3PCI is illustrated in Figure 1-1.
Figure 1-1. Typical 3PCI Power Controller
The 3PCI is a three-phase, phase-fired power controller, and can operate with a wide variety of input signals
and line voltages. The 3PCI’s output voltage is proportional to the control input signal, with the output voltage
regulated to ±0.5% with a ±10% line voltage change. The 3PCI features cosine intercept, hard-gate firing
which provides high immunity to possible SCR firing disturbances. Other features include the following:
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input isolation from ground (galvanic)
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soft-start capability
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automatic restart circuitry
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50/60 Hz operation without any required changes.
Terminals are provided to permit connection of a variety of external control methods. Terminals, dimensions,
and key components are illustrated in Figure 1-2.