<h2>Overview</h2>
<p>The <strong>Reliance Electric 1SU41020</strong> is a 20 horsepower AC inverter drive from the SP500 series, designed for three-phase motor speed control in industrial environments. Built on pulse-width-modulated (PWM) technology, this drive offers efficient, adjustable-speed operation with volts-per-hertz regulation. The SP500 line, while discontinued by Rockwell Automation in 2009, remains widely deployed in legacy systems and is valued as a cost-effective replacement for existing installations.</p>
<h2>Key Features</h2>
<ul>
<li>NEMA 1 (chassis) enclosure, size D with compact dimensions (18.31" H × 11.28" W × 7.83" D)</li>
<li>Built-in 4-character display, 6-key keypad, and 8 status LEDs for local control</li>
<li>Three-phase PWM inverter with IGBT bridge for reduced acoustic noise</li>
<li>Adjustable speed control via local keypad or terminal strip input</li>
<li>Integrated protection: overcurrent, overtemperature, short-circuit, over/undervoltage, ground fault</li>
<li>MOV voltage suppressors on input for transient protection</li>
</ul>
<h2>Technical Specifications</h2>
<ul>
<li><strong>Power Rating:</strong> 20 HP</li>
<li><strong>Input Voltage:</strong> 380–460 VAC, 3-phase</li>
<li><strong>Input Current:</strong> 32.7 A</li>
<li><strong>Output Current:</strong> 27.0 A</li>
<li><strong>Control Method:</strong> Pulse-Width Modulation (PWM)</li>
<li><strong>Frequency Range:</strong> 0–240 Hz</li>
<li><strong>Power Loss:</strong> 600 W</li>
<li><strong>Operating Temperature:</strong> 0° to 40°C</li>
<li><strong>Enclosure Type:</strong> NEMA 1 (Chassis)</li>
<li><strong>Enclosure Size:</strong> D</li>
<li><strong>Dimensions:</strong> 465.2 mm H × 286.5 mm W × 198.9 mm D (18.31" × 11.28" × 7.83")</li>
<li><strong>Weight:</strong> 15.3 kg (34 lbs)</li>
<li><strong>Enclosure Rating:</strong> IP20 equivalent</li>
<li><strong>Certifications:</strong> UL Listed, IEC Certified</li>
</ul>
<h2>Typical Applications</h2>
<p>The 1SU41020 is ideal for systems requiring high-horsepower AC motor speed control in moderate environmental conditions. Common applications include:</p>
<ul>
<li>Industrial pump and fan drives</li>
<li>Compressor speed regulation</li>
<li>Machine tool spindle control</li>
<li>Conveyor and material handling systems</li>
<li>Legacy system replacements and upgrades</li>
</ul>
<h2>Compatibility & Replacements</h2>
<h3>Compatible With</h3>
<ul>
<li>Three-phase AC motors rated 20 HP and lower</li>
<li>380–460 VAC, 50/60 Hz industrial power supplies</li>
<li>Standard motor terminal boxes with soft-start or across-the-line motor starters</li>
<li>PLC and programmable controller I/O for remote speed command</li>
</ul>
<h3>Replaces / Drop-In Replacement For</h3>
<p>The 1SU41020 is a direct replacement for other SP500 series 20 HP units operating at 380–460 VAC. Verify exact model compatibility with your system integrator before ordering, as some SP500 variants may have different voltage or frequency specifications.</p>
<h3>Works With</h3>
<ul>
<li>Analog 0–10 VDC or 4–20 mA speed reference signals</li>
<li>Digital I/O for forward/reverse and run/stop control</li>
<li>Manual keypad adjustment via local 6-key interface</li>
<li>Terminal strip wiring for direct AC input and motor output connections</li>
<li>Standard SP500 installation and operation manual (D2-3356-6)</li>
</ul>
