Edwards EDS200 - User Manual

Need help?

Do you have a question about the Edwards EDS200 and is the answer not in the manual?

Overview

Function Description
Important Technical Specifications
Usage Features
Maintenance Features

The provided document is an instruction manual for a Flush Kit designed for Edwards EDS200, EDS300, and EDS480 vacuum pumps.

Function Description

The Flush Kit is an accessory designed to remove deposits that may form within the pump chamber of Edwards vacuum pumps during operation. It achieves this by flushing the pump with water or a suitable solvent. The kit allows for the controlled introduction of a required amount of solvent into the inlet of the vacuum pump to clean internal depositions.

The Flush Kit is available in three variants:

Flush kit / Solenoid valve ATEX: This variant includes an ATEX-certified solenoid valve, suitable for use in potentially explosive atmospheres.
Flush kit / Solenoid valve: This variant includes a standard solenoid valve.
Flush kit / Manual valve: This variant includes a manual valve for solvent flow control.

All variants include a visual flowmeter with a manually adjustable valve and a non-return valve. The kit regulates, automatically/manually shuts off, and provides visibility of the solvent flow into the vacuum pump's inlet. For optimal cleaning, the manual recommends installing an inlet purge kit in conjunction with the flush kit.

The selection of the solvent is crucial and depends on the process medium. Users must ensure the chosen solvent is compatible with the materials of construction of the vacuum pump to prevent damage. The manual recommends Xylene and Water as suitable solvents. To maximize the cleaning effect, the solvent should remain at least partly in the liquid phase inside the pump, which can be achieved by increasing the inlet pressure of the vacuum pump, often by using an inlet purge accessory.

Important Technical Specifications

The manual provides technical data for the Solenoid valve ATEX and the standard Solenoid valve variants of the flush kit.

Solenoid valve ATEX:

ATEX rating: II 2G Ex mb IIC T4 Gb; II 2D Ex tb IIIC T130 °C Db. This indicates its suitability for hazardous environments, specifically for gases (Group II, Category 2G, Ex mb, gas group IIC, temperature class T4) and dust (Group II, Category 2D, Ex tb, dust group IIIC, maximum surface temperature T130 °C).
Pressure range: 0 to 2.45 bar.
Power: 10.1 W.
Voltage: 24 V d.c.
Insulation class: H 180 °C.
IP rating: IP65, indicating protection against dust ingress and low-pressure water jets from any direction.
Connection: DIN 43650A.
Supplied cable length: 3 m.

Solenoid valve (standard):

ATEX rating: NA (Not Applicable).
Pressure range: 0 to 3.5 bar.
Power: 18 W.
Voltage: 24 V d.c.
Insulation class: H 180 °C.
IP rating: IP65.
Connection: DIN 43650A.
Supplied cable length: 3 m.

Materials in contact with the solvent (common to both solenoid valve types):

Stainless Steel
Borosilicate glass
Viton
PTFE

Maximum allowable flow rates (water as a solvent) for different pump models and flushing options:

Option 1 (Continuous 10 minutes flush):

EDS200 (Inlet pressure 60 mbar with inlet purge kit): Solvent flow 0.7 l/min, Liquid phase ratio (out/in) ≈ 0.8.
EDS300 (Inlet pressure 50 mbar with inlet purge kit): Solvent flow 1.8 l/min, Liquid phase ratio (out/in) ≈ 0.9.
EDS480 (Inlet pressure 30 mbar with inlet purge kit): Solvent flow 2.5 l/min, Liquid phase ratio (out/in) ≈ 0.9.

Option 2 (1 minute flush, 3 minutes wait, repeat up to 5 times):

EDS200 (Inlet pressure 60 mbar with inlet purge kit): Solvent flow 3.3 l/min, Liquid phase ratio (out/in) ≈ 0.9.
EDS300 (Inlet pressure 50 mbar with inlet purge kit): Solvent flow 3.3 l/min, Liquid phase ratio (out/in) ≈ 0.85.
EDS480 (Inlet pressure 30 mbar with inlet purge kit): Solvent flow 3.3 l/min, Liquid phase ratio (out/in) ≈ 0.85.

Usage Features

The Flush Kit offers flexibility in installation and commissioning:

Installation: The kit can be installed on the pump either without a canopy or with a canopy (for EDS200 and EDS300 pumps). The installation process involves:

Preparing the Flush kit / Solenoid valve by attaching its bracket.
Replacing a plug screw on the pump with a supplied adapter.
Installing the Flush kit / Solenoid valve on the pump by loosening a hex head cap screw on the top cover, sliding the bracket in, and then tightening the screw.
Fitting the Non-Return Valve (NRV) to the pump by loosening its nut, fitting it into the adapter, and then tightening the nut.
Tightening the screw on the top cover (or canopy) to firmly hold the bracket. Electrical connections for ATEX solenoid valves must conform to EN60079-14 and local regulations.

Commissioning: Before commissioning, users are warned about potential hazards such as electric shock, hot surfaces, hazardous vapors, and noise levels. Proper ventilation and unobstructed exhaust lines are emphasized. The solvent supply is connected to a G1/4" port on the solenoid or manual valve. The flow rate is manually adjustable via a valve on the flowmeter.

Two flushing options are provided:

Option 1: Continuous flush for 10 minutes. During this, the motor current should not exceed 1.2 times the maximum motor current.
Option 2: Intermittent flush, consisting of 1-minute flushes followed by 3-minute waits, repeated up to 5 times. During this, the motor current should not exceed 1.5 times the maximum motor current.

Setting the flow rate (especially for non-water solvents):

Ensure the inlet purge kit (if installed) is open to achieve an inlet pressure of 30 to 60 mbar.
Close the manual valve on the flowmeter.
Open the solenoid valve.
Open the manual valve until the desired flow rate is achieved.
Start a timer and monitor pump operation and motor current to ensure it stays within limits.
If the pump makes a "pinking" noise or noise level rises, reduce the solvent flow rate.
Repeat timing tests to determine the permissible flow rate without exceeding motor current limits.
Once set, the flow rate does not need constant adjustment; the solenoid valve controls start/stop.
During flushing, monitor the solvent leaving the exhaust to ensure it is mostly in the liquid phase.

Maintenance Features

The manual implicitly highlights maintenance considerations through its safety warnings and operational guidelines:

Safety during maintenance/installation:

Electrical Safety: Disconnect mains power and implement tag out/lock out procedures before working on the vacuum pump to prevent electric shock. Electrical connections must be performed by a trained electrician.
Thermal Safety: Allow the vacuum pump to cool down before installing the flush kit to avoid burns from hot surfaces (temperatures can exceed 70 °C).
Personal Protective Equipment (PPE): Wear appropriate protective equipment, especially when handling hazardous substances that the pump may have processed.
Hazardous Vapors: Be aware of hazardous vapors that can escape from the exhaust at operating temperatures. Ensure adequate ventilation.

Operational considerations for pump longevity:

Motor Protection: High solvent flow can cause the pump motor to exceed its maximum current and trip motor protection, especially if a frequency converter is not installed. The commissioning procedure emphasizes monitoring motor current to prevent damage.
Solvent Compatibility: Users are responsible for selecting solvents compatible with the pump's materials of construction to prevent damage.
Noise Level Monitoring: An increase in noise level or a "pinking" noise during flushing indicates pump distress, requiring a reduction in solvent flow rate.

Disposal: At the end of its life, the contaminated solvent and the flush kit must be disposed of safely, in accordance with all local and national safety and environmental regulations. This implies that the kit itself is subject to disposal guidelines, and any residual solvent within it or collected during flushing must be handled as hazardous waste.