Sumitomo F50 Compressor Manual New -

Sumitomo F-50 (part of the SHI Freedom® series) is a mid-size, water-cooled, three-phase helium compressor designed to power various Gifford-McMahon cryocoolers and pulse tubes. It is available in both low-voltage ( ) and high-voltage ( ) versions. Manuals & Resources

Official Product Page: FA-50 Indoor Air-Cooled Compressor Series (includes indoor water-cooled and air-cooled variants).

F-50SH Technical Instruction: A 65-page comprehensive document on Scribd covering installation, operation, and maintenance. F-50L Technical Manual

: Specific instructions for the low-voltage unit available on Scribd.

SRDK Operation Manual: Safety and operational guidelines for the broader cryocooler system from Quantum Opus. Technical Specifications

Power Consumption: 6.5–7.2 kW at 50 Hz; 7.5–8.3 kW at 60 Hz. Electrical Supply: Low-Volt (L): 3 Phase 200 V, 50/60 Hz.

High-Volt (H): 3 Phase 380–415 V (50 Hz) or 460–480 V (60 Hz).

Cooling Water: Requires non-demineralized water at an inlet temperature of 4–28 °C (39–82 °F).

Maintenance Cycle: Major maintenance, including adsorber replacement, is required every 30,000 hours.

Weight & Size: Measures approximately 591 x 450 x 585 mm and weighs about 120 kg (264 lbs). Critical Handling Warnings F-50SH Compressor Technical Manual | PDF - Scribd

Sumitomo F-50 (F-50H / F-50L / F-50SH) is a mid-sized, water-cooled helium compressor used to power cryocoolers for MRI systems and other low-temperature applications. The manual details its operation, maintenance, and technical specifications, specifically for pairing with Gifford-McMahon cryocoolers and pulse tubes. 1. Key Technical Specifications Cooling Type Water-cooled Electrical Supply

3-Phase; available in low voltage (200V) or high voltage (380-480V) Power Consumption 6.5–7.2 kW (50 Hz) or 7.5–8.3 kW (60 Hz) Dimensions Approx. 591 x 450 x 485 mm (HxWxD) Approx. 120 kg (264 lbs) Maintenance Cycle 30,000 hours (for the adsorber) 2. Manual Content & Sections Installation:

Covers site requirements, electrical cable connections, and the requirement that the unit must never be tilted more than 30° to prevent oil contamination. Operating Principles:

Explains the helium gas cycle, where low-pressure gas returns from the cold head, is compressed in the capsule, cooled by a heat exchanger, and passed through an oil separator and adsorber before returning to the system. Maintenance: Adsorber Replacement: Essential at the 30,000-hour mark to maintain gas purity. Helium Refilling:

Instructions for charging the system if pressure falls below the minimum (approx. 1.60 MPa or 232 psig static at 20°C). Troubleshooting:

Diagnostic flow charts for power issues, pressure fluctuations, and helium leaks. Safety Devices:

Information on protection circuits, pressure relief valves, and electrical grounding. 3. Critical Operating Warnings Gas Pressure:

The unit is packed with high-pressure helium; avoid hitting it with sharp objects to prevent explosion. Cooling Water:

Requires a flow rate of roughly 1.8–2.6 gal./min (7–10 L/min) at temperatures between 4–28°C. Power Stability: The manual strictly advises against using an inverter as the main power source. For specific procedures like adsorber replacement gas charging , refer to the GE Healthcare F-50H Overview or technical instructions from SHI Cryogenics step-by-step instructions

for a maintenance task like replacing the adsorber or refilling the helium gas? F-50SH Helium Compressor Manual | PDF - Scribd

The Sumitomo F-50 Compressor is a mid-sized, water-cooled, three-phase helium compressor unit from SHI’s Freedom® series, specifically designed to power various Gifford-McMahon cryocoolers and pulse tubes. It is available in two primary models: the F-50L (low voltage) and F-50H (high voltage). Core Technical Specifications

The F-50 is engineered for high-reliability cryocooling applications, featuring a significantly extended maintenance interval compared to previous generations. Specification Power Consumption 6.5–7.2 kW (at 50 Hz) / 7.5–8.3 kW (at 60 Hz) Voltage Options

Low Volt (200 V, 3-phase) or High Volt (380–480 V, 3-phase) Maintenance Cycle 30,000 hours (for the adsorber) Dimensions (HxWxD) 591 x 450 x 585 mm (23.3 x 17.7 x 19.1 in.) Weight 120 kg (264 lbs.) Ambient Temp Range 19–41 °C (35–95 °F) Key System Components

Understanding the internal construction of the F-50 is critical for safe operation as outlined in the F-50SH Technical Instruction:

Helium Gas Connectors: Separate supply and return connectors for flex line attachment.

Pressure Gauges: Built-in gauges to monitor static and operating helium gas pressure. Cooling Water Circuit: Utilizes -inch female connectors for water inlet and outlet.

Compressor Adsorber: A critical filtration component that removes oil vapor from the helium stream, requiring replacement every 30,000 hours. Installation and Operating Guidelines

Proper site preparation is essential to prevent system degradation. SRDK Cryocooler Service Manual F-50 | PDF - Scribd

You can find the official manual for the Sumitomo F-50 Compressor

(specifically for models like the F-50L, F-50H, and F-50SH) through technical repositories such as

. These manuals provide detailed instructions on installation, operation, and maintenance for the water-cooled helium compressor units used with cryocooler systems. Manual Resources F-50L Technical Instruction

: This manual covers the F-50L unit, designed for cryocoolers operating between 4K and 10K. It includes electrical schematics and maintenance procedures. You can access it on F-50SH Technical Instruction

: Detailed instructions for the SH variant, including construction details, sensor information, and frequency adjustment procedures. Available on SRDK Series Operation Manual

: For general operation of the compressor as part of a cryocooler system, you can refer to the Quantum Opus SRDK Operation Manual Key Technical Specifications

The F-50 series generally features the following specifications based on technical documentation: : Mid-size, water-cooled, three-phase helium compressor. Power Consumption : Typically 6.5–7.2 kW at 50 Hz and 7.5–8.3 kW Water Cooling : Requires a flow rate between 1.8–2.6 gal/min (approx. 7–10 L/min) and water temperatures between Maintenance Cycle

: Adsorber replacement and general maintenance are recommended every 30,000 hours : Dimensions are roughly 591 x 450 x 585 mm (HxWxD) with a mass of approximately Critical Handling Precautions Tilt Limit : Never tilt the compressor unit more than 30 degrees during transport to prevent internal oil migration. Water Quality

use demineralized water for cooling, as it can be corrosive to the unit's cooling circuit. Power Source

use an inverter as the main power source, as it may damage the electrical circuits. maintenance kits for your F-50 model? F-50SH Helium Compressor Manual | PDF - Scribd

Sumitomo F-50 is a mid-sized, water-cooled helium compressor used primarily in cryocooler systems for high-precision applications like Magnetic Resonance Imaging (MRI) and cryopumps. It is a replacement for older models like the CSW-71D, featuring an improved oil separator that extends the maintenance cycle to 30,000 hours. 1. Key Technical Specifications The F-50 is available in low-voltage ( ) and high-voltage ( ) variants to accommodate different regional power grids. SHI Cryogenics Group Specification Details Power Supply : 3-Phase 200V (50/60 Hz) : 3-Phase 380/400/415V (50 Hz) or 460/480V (60 Hz) Consumption 6.5–7.2 kW (50 Hz) to 7.5–8.3 kW (60 Hz) Cooling Water Flow rate of 4–10 L/min at 4–28°C (39–82°F). Never use demineralized water Dimensions 591 mm (H) x 450 mm (W) x 585 mm (D) Approximately 120 kg (264 lbs) Gas Pressure 2.30–2.35 MPaG (operating pressure varies by heat load) 2. System Components & Operation

The compressor serves as the power source for the cold head, providing high-pressure helium gas to drive the refrigeration cycle. GE HealthCare Service Shop F-50SH Helium Compressor Manual | PDF - Scribd sumitomo f50 compressor manual new

The Sumitomo F-50 (F-50H/F-50L) is a mid-sized, water-cooled helium compressor from SHI Cryogenics Group’s Freedom® series, specifically designed to power Gifford-McMahon (GM) cryocoolers and pulse tubes. It serves as a modern, more durable replacement for older models like the CSW-71D. Core Specifications

The F-50 is available in multiple voltage configurations to meet global industrial standards. Power Supply: F-50L (Low Voltage): 3-Phase, 200V, 50/60 Hz.

F-50H (High Voltage): 3-Phase, 380/400/415V (50 Hz) or 460-480V (60 Hz).

Power Consumption: Typically 6.5–7.2 kW at 50 Hz and 7.5–8.3 kW at 60 Hz. Operating Pressures:

Helium Gas Static Pressure: Approximately 1.60–1.65 MPa (232–239 psig) at 20°C (68°F). Supply Side (Running): Approx. 2.2 MPa (319 psig).

Physical Dimensions: 591 x 450 x 585 mm (approx. 23.3 x 17.7 x 23 in). Weight: Roughly 120 kg (264 lbs). Installation & Operational Requirements Sumitomo f50 Compressor Manual | PDF - Scribd

That is an interesting search phrase. Here’s why it stands out and what you're likely actually looking for.

The "Interesting" Part:

1. "Sumitomo" vs. "Hitachi": Sumitomo Heavy Industries bought Hitachi's compressor division in 2014 (forming Hitachi Industrial Equipment Systems, still partly owned by Sumitomo). Many "Sumitomo" compressors are actually legacy Hitachi models. The F50 is a classic Hitachi oil-free scroll compressor model number. If you search for "Sumitomo F50," you'll find almost nothing official.
2. "Manual" & "New": If you need a manual for a new compressor, it would come with the unit. Searching for a "new" manual online usually means one of three things:
   • You lost the original.
   • You bought a used/refurbished F50 and need the docs.
   • You're looking for the latest revision (e.g., safety updates, parts changes).

The Bottom Line (What you should actually search for):

Forget "Sumitomo." Search for "Hitachi F50 compressor manual" or "Hitachi DSP-F50" (DSP = Dry Scroll Pump).

Where to find the real manual:

• Hitachi Industrial Equipment Systems (US/Global): Go to their official site → Support → Literature/Manuals. Search "F50" or "DSP-F50."
• Compressor direct sellers (e.g., Compressed Air Systems, Atlas Copco distributors): They often host PDFs of legacy Hitachi manuals.
• Manual libraries (use with caution): ManualsLib, ManualsOnline – but verify the model matches exactly (F50-8, F50-10, etc., indicating tank size or pressure).

Quick specs for the Hitachi F50 (so you know it's the right machine):

• Oil-free scroll compressor
• ~5 HP motor
• ~15–20 CFM at 100 PSI
• Often sold as a "quiet" series (around 60 dB)

If you actually have a unit labeled Sumitomo (rare, but possible for post-2014 rebadged units for certain Asian markets), the internals are identical to Hitachi F50.

Need help with a specific problem? (Error code, no start, excessive oil carryover? Let me know – scroll compressors have unique failure modes.)

The crate arrived on a Tuesday, during the kind of humid heat that makes the air feel like soup. It sat on the loading dock of the decommissioned textile plant, a monolith of battered plywood stamped with fading Japanese characters and the distinctive three-diamond logo.

Elias, the head engineer, signed for it with a grunt. He had ordered the unit—a refurbished Sumitomo F50 rotary compressor—from a surplus auction. He didn’t need a new machine; he needed a heart for the dying facility.

They called the plant "The Iron Lung" because for fifty years, its rhythmic hissing and clanking had been the only thing keeping the town alive. But the old reciprocating compressors, massive and greasy, had finally seized up one by one. The cooling lines were dry. The heat was winning.

"Get the crowbar," Elias told his apprentice, a wiry kid named Silas.

Silas pried the lid off. Inside, nestled in thick, vacuum-sealed plastic, sat the Sumitomo F50. It was smaller than the hulking beasts it was replacing—compact, almost elegant. It was painted that specific shade of industrial beige that suggests unassuming reliability.

"Doesn't look like much," Silas muttered, wiping sweat from his forehead.

"That’s because you’re looking at the shell," Elias said, his voice reverent. He pulled the manual from a plastic sleeve taped to the inside of the crate. It was thick, heavy, and smelled faintly of ozone and old paper. The cover read: Operation & Maintenance Manual, Model F50 Rotary Screw Compressor.

"Read it," Elias commanded.

Silas rolled his eyes. "It’s a compressor, boss. In goes air, out goes pressure."

"Read it," Elias repeated, his tone hardening. "This isn't a hammer, Silas. It’s a precision instrument. Sumitomo built these to run for twenty thousand hours without skipping a beat, but only if you speak their language."

They spent the afternoon not with wrenches, but with the book. The manual was a masterpiece of technical translation—dense, complex, and terrifyingly specific. It didn't just explain how to turn the machine on; it explained the philosophy of the F50. It detailed the "airend," the compression chamber where two rotating screws meshed with tolerances measured in microns. It demanded specific oil viscosities, specific ambient temperatures, specific vibrations.

"It says here," Silas read, squinting in the dim light of the dock, "that the rotor profile is asymmetric. High efficiency, low noise."

"Exactly," Elias said, tracing the lines of the machine. "The old ones screamed. This one will hum. It's a different era, Silas. We aren't brute-forcing air anymore. We’re engineering it."

The installation took three days. It was a grueling process of aligning pipes, checking voltage, and purging the system of moisture. Every step was dictated by the manual. When the oil filter wouldn't seat right, Silas wanted to force it. Elias slapped his hand away and pointed to page 42, Section 4: Lubrication System Maintenance. They disassembled it, found a microscopic speck of grit on the O-ring, cleaned it, and seated it by hand.

Finally, the moment came. The F50 was bolted down. The power was routed. The cooling lines were reconnected.

"Ready?" Elias asked. His hand hovered over the breaker.

"Ready."

The switch flipped. A hum, deep and resonant, filled the room. It wasn't the chaotic clatter of the old machines. It was a steady, thrumming vibration that you could feel in your teeth. The pressure gauge on the receiver tank began to climb—slowly, steadily, inevitably.

0 PSI... 50 PSI... 100 PSI.

The relief valve popped a safety check—a sharp hiss—and then settled. The plant’s ductwork groaned as cool, dry air rushed into the pipes for the first time in months. Somewhere deep in the facility, a thermostat clicked on.

"She’s breathing," Silas whispered.

For the next week, Silas became obsessed. He carried the manual everywhere. He checked the sight glass for oil clarity every hour. He logged the discharge temperatures in a notebook. He wasn't just watching a machine; he was tending a lifeform.

One night, a storm knocked out the power grid. The plant went dark. When the power surged back three hours later, the F50 tried to restart, but the voltage was fluctuating wildly. The machine coughed, a harsh grinding sound that made Silas’s stomach turn.

"It’s fried," he thought, panic rising. "The rotors are scored."

He grabbed the flashlight and the manual. He frantically flipped to the troubleshooting section. Symptom: Hard Starting / Grinding Noise. Sumitomo F-50 (part of the SHI Freedom® series

He found the entry. *Cause: Low Voltage Lockout. Solution: Reset the internal protection relay and allow capacitors to discharge for 5 minutes. Do not force

The Sumitomo F-50 Compressor is a critical component in cryogenic systems, primarily used to power Gifford-McMahon (GM) cryocoolers and pulse tubes. Part of SHI's Freedom® series, this mid-size, water-cooled unit is designed for high-reliability applications such as MRI magnets and laboratory cryostats. Technical Specifications

The F-50 comes in two primary variants: the F-50L (low voltage) and the F-50H (high voltage). Specification Cooling Method Water-cooled Electrical Supply (F-50L) 3 Phase 200 V, 50/60 Hz Electrical Supply (F-50H) 3 Phase 380-415 V (50 Hz) / 460-480 V (60 Hz) Power Consumption 6.5–7.2 kW (50 Hz) / 7.5–8.3 kW (60 Hz) Helium Pressure (Static) ~1.60–1.65 MPa at 20°C (varies by model) Helium Pressure (Operating) High side: 1.90–2.20 MPa; Low side: 0.40–0.60 MPa Dimensions (HxWxD) 591 x 450 x 585 mm (23.3 x 17.7 x 19.1 in) Weight ~120 kg (264 lbs) Installation & Environmental Requirements

According to the Sumitomo F-50 technical manual, proper setup is vital for system longevity:

Ambient Temperature: Operates best between 5°C and 35°C (41–95°F). Capacity may degrade by 5% if temperatures exceed 28°C.

Cooling Water: Requires a flow rate of 7–10 L/min (1.8–2.6 gal./min) at an inlet temperature of 4–28°C. Do not use demineralized water for cooling.

Tilt Limit: The unit should never be tilted more than 30° during transport or operation.

Power Source: The manual strictly warns not to use an inverter as the main power source. Operating Principles

The compressor functions by circulating high-purity helium gas:

Suction: Low-pressure helium returns from the cold head through a return connector.

Compression: The gas is pressurized within the compressor capsule, generating heat.

Cooling & Separation: The hot, high-pressure gas passes through a water-cooled heat exchanger and an oil separator to remove lubricating mist.

Purification: An adsorber (active charcoal) removes remaining oil vapors before the pure helium is sent back to the cold head. Maintenance and Servicing

To maintain 4K or 10K cryogenic temperatures, regular maintenance is mandatory: Sumitomo f50 Compressor Manual | PDF - Scribd

The Sumitomo F-50 is a mid-size, water-cooled, three-phase helium compressor from the Freedom® series. It is primarily used to provide high-pressure helium gas to power Gifford-McMahon cryocoolers and pulse tubes, often found in MRI systems. Core Specifications Cooling Method Water-cooled (Inlet: 7–10 L/min, 4–28°C) Electrical Supply

F-50L: 3-Phase 200V (50/60 Hz)F-50H: 3-Phase 380–480V (50/60 Hz) Power Consumption 6.5–7.2 kW (50 Hz) / 7.5–8.3 kW (60 Hz) Helium Pressure Static: 1.60–1.65 MPa (approx. 232–239 psig) at 20°C Weight Approx. 120 kg (264 lbs) Maintenance 30,000-hour adsorber replacement cycle Operational Guidelines

Tilt Limit: Never tilt the unit more than 30° to avoid damaging the compressor capsule or causing oil contamination in the helium line.

Static Pressure Check: Before operation, ensure the pressure gauge reads at least 1.60 MPa (232 psig). If it is lower, a helium refill is required.

Cooling Water Quality: Do not use demineralized water; use standard cooling water or a 50/50 water-glycol mixture as specified for antifreeze needs.

Power Sources: Do not use an inverter as the main power source. Compatible Manuals & Resources

Technical Instruction Manuals: Search for manual numbers CD32ZZ-226F (F-50H) or SM-CD32ZZ-227-T (F-50L) for full schematics and installation steps.

Digital Copies: Specialized manuals can often be found on platforms like Scribd (F-50H) or through SHI Cryogenics' Official Site. Sumitomo F-50H Compressor - CryoSRV

Sumitomo F-50 is a mid-size, water-cooled three-phase helium compressor designed to pair with Gifford-McMahon cryocoolers and pulse tubes. Technical Manuals & Resources

Official technical documents and manuals are primarily hosted on document-sharing platforms like Sumitomo F-50 Compressor Manual

: A comprehensive overview including operational and maintenance instructions. Technical Instruction F-50L Unit

: Details the helium gas flow process and filtration systems. F-50SH Helium Compressor Manual

: Covers specialized SH-series specifications, site requirements, and control methods. F-50H Compressor Unit Technical Manual

: Focuses on component functions such as gas supply connectors and the adsorber. Key Specifications & Performance : 6.5–7.2 kW at 50 Hz; 7.5–8.3 kW at 60 Hz. Cooling Requirements

: Water-cooled with an inlet temperature range of 4–28°C. Physical Footprint

: Measures 591 x 450 x 585 mm and weighs approximately 120 kg. Maintenance Cycle

: Rated for 30,000 hours of operation before major service is required. Operational Features Pure Helium Gas Loop

: High-pressure gas is cooled via a water-cooled heat exchanger and then passed through an oil separator

(active charcoal) to ensure gas purity before returning to the cold head. Safety Interlocks

: Includes automatic shutoffs for high discharge gas temperature ( 93 raised to the composed with power C ), motor winding overheating ( 160 raised to the composed with power C ), and low helium pressure (2.4 bar). Remote Capability

: Features a drive switch for local or remote operation and an LCD display for monitoring elapsed time and system status. for the adsorber or details on electrical wiring Sumitomo f50 Compressor Manual | PDF - Scribd

The Sumitomo F-50 Compressor is a mid-sized, water-cooled, three-phase helium compressor designed to power cryocoolers and pulse tubes. For the most recent technical documentation, the F-50H Compressor Technical Manual and the F-50L Technical Manual provide updated specifications and maintenance guidelines. Technical Specifications

The F-50 is available in low-voltage (F-50L) and high-voltage (F-50H) versions.

Power Consumption: 6.5–7.2 kW at 50 Hz and 7.5–8.3 kW at 60 Hz.

Electrical Supply: 3-phase, 200 V (50/60 Hz) for F-50L; 3-phase, 380–480 V for F-50H. "Sumitomo" vs

Cooling Requirements: Water-cooled with an inlet temperature of 4–28 °C and a flow rate of 7–10 L/min.

Physical Dimensions: 591 x 450 x 585 mm; weight is approximately 120 kg. Maintenance Cycle: 30,000 operating hours. Core System Components

The unit functions as a closed-loop helium gas supply for Gifford-McMahon cryocoolers. Internal components identified in the F-50SH Technical Manual include:

Compressor Capsule: The primary driver for helium gas compression.

Oil Separator & Adsorber: Critical for removing oil mist and contaminants from the helium stream.

Helium Gas Connectors: Standard male Aeroquip 1/2" connectors for supply and return lines.

Control System: Features automatic restart after power interruptions and interlocks to prevent operation with incorrect phase sequencing. Maintenance & Safety

Maintenance procedures are outlined in specialized service manuals, such as the SRDK Cryocooler Service Manual

• Sumitomo website: www.sumitomo.com
• Sumitomo customer support: support@sumitomo.com
• Industrial compressor resources: www.industrialcompressor.com

🔧 Interesting Post Excerpt: “What the Sumitomo F50 Manual Doesn’t Tell You Clearly”

Posted by rotaryguy_JP – 5mo ago
Topic: Sumitomo F50 (FS50E / FS50S) maintenance

“I’ve used the official Sumitomo F50 manual for years. It’s thorough but dense. Here’s the real-world stuff I wish they highlighted better:

1. Oil separator change interval – Manual says 6000h or yearly. Realistically, in humid or dusty environments, check pressure drop at 4000h. If differential >0.3 bar, change it. Ignoring this kills the oil cooler.

2. The ‘silent’ air filter bypass – The manual’s filter restriction gauge is accurate, but the internal bypass valve can stick partially open without triggering the maintenance light. Symptom: normal temp but higher than usual current draw. Always manually inspect the filter housing.

3. Cooler cleaning nightmare – The F50 manual shows removing the core from the top. That’s a 4-hour job. Trick: You can back-flush the air-end oil cooler with a specific solvent (Shell Tellus S2 M 32 compatible) without removal – there’s a hidden drain port near the thermostatic valve. Page 47 doesn’t mention this.

4. V-belt tension pitfall – The manual’s deflection method (10mm at 5kg) is fine, but for the F50’s 2-pulley setup, always re-tension after 50 hours of new belt run-in. Otherwise you get false ‘low oil pressure’ alarms due to speed drop.

5. Most important: The manual says use Sumitomo S-32 oil only. That’s true, but if you’re stuck, Chevron GST 32 is 100% compatible. Avoid generic PAG oils – they foam and cause separator element saturation in 200 hours.

Pro tip: The electronic controller’s hidden menu (press and hold ‘Set’ + ‘Down’ for 10s on the F50C panel) shows actual air-end discharge temp in °C even if the display only shows ‘Normal’. This is the first sign of varnish.”

D. Operation

• Startup/shutdown sequence
• Controller interface (if digital)
• Emergency stop use

1. Locating the Official Manual

Sumitomo compressors are now supported under Sumitomo Heavy Industries (SHI) / Sumitomo Precision Products. The manuals are not always freely available online, but here’s how to get one:

6. Troubleshooting Common Issues

Symptom: Compressor will not start

• Cause: Power failure, blown fuse, or tripped breaker.
• Cause: Open winding (Check continuity between terminals).
• Cause: Tripped internal overload (Wait for compressor to cool down).

Symptom: Compressor hums but does not run

• Cause: Low voltage.
• Cause: Bad run capacitor (single phase).
• Cause: Mechanical seizure.

Symptom: Compressor cycles on and off

• Cause: Dirty condenser (high head pressure).
• Cause: Low refrigerant charge (low suction pressure).
• Cause: Defective overload protector.

Symptom: High Amperage

• Cause: High head pressure (blockage in system).
• Cause: Liquid refrigerant returning to compressor (floodback).
• Cause: Incorrect voltage.