Electronically Controlled Drains Electronically Controlled Drains

Product Overview

The ROSS Controls Electronically Controlled Drains are programmable timer-operated drain valves for automatic condensate removal from FRL filter bowls. Unlike float-operated automatic drains that respond to condensate level, the series operates on user-set time intervals, opening the drain valve for a programmable duration at programmable intervals regardless of condensate level. This approach is used when consistent timed drain cycles are required for system integration, energy auditing, or drainage management in high-moisture environments.

The Series is available in 24 VDC and 110-120 VAC, 50/60 Hz models, in 1/4, 3/8, and 1/2 inch pipe sizes with both NPT (NPTF) and G (BSPP) thread configurations. The drain timer is adjustable: drain time is settable from 0.5 to 10 seconds, and the drain interval is settable from 0.5 to 45 minutes, providing wide flexibility for matching the drain cycle to the application condensate production rate.

The drain valve body is forged brass with a 2/2 normally closed direct-acting solenoid valve construction and a 3/16-inch (4.8 mm) orifice. Electrical connection is via DIN 43650A (ISO 440/6952) connector, the standard industrial solenoid connection type. Maximum operating pressure is 230 psig (15.8 bar), and the drain handles all FRL bowl types.

The Series is the appropriate choice for applications where condensate production is predictable and high, where integration with a machine control system is required, where drain cycle documentation is needed for energy management, or where a float-operated drain may be insufficiently reliable in high-particulate environments. Twelve model variants provide complete coverage across voltage, pipe size, and thread type combinations.

Key Engineering Features

• Programmable Drain Time and Interval - Drain time is adjustable from 0.5 to 10 seconds; drain interval is adjustable from 0.5 to 45 minutes, allowing precise calibration of drain frequency to match condensate production rates in the specific installation.
• 24 VDC and 115 VAC Models - Available in both 24 VDC and 110-120 VAC, 50/60 Hz configurations to match the available control power supply in the machine or panel where the FRL is installed.
• 1/4, 3/8, and 1/2 Inch Pipe Sizes with NPT and G Threads - Twelve model variants cover all common FRL drain port sizes in both North American NPT and international G (BSPP) thread configurations, providing global applicability.
• Forged Brass Valve Body - The Series valve body is forged brass with a 3/16-inch (4.8 mm) orifice, providing robust construction for condensate service in industrial compressed air systems rated to 230 psig (15.8 bar).
• DIN 43650A Electrical Connection - Uses the standard DIN 43650A (ISO 440/6952) solenoid connector, ensuring compatibility with industrial wiring practices and enabling easy field replacement of the solenoid coil without special connectors.
• Compatible with All FRL Bowl Types - The Series electronically controlled drain is compatible with all ROSS FRL bowl types (polycarbonate and metal), providing a single drain solution across the entire FRL filter product range.
• Low Power Consumption - Maximum current consumption of 4 mA (coil), enabling integration into control systems with tight power budgets and remote PLC output cards without exceeding output current ratings.

Technical Specifications

General Specifications

Temperature Ratings

The Series drain operates across a wide temperature range suitable for typical industrial compressed air environments.

Important: Do not expose the polycarbonate components of compatible FRL filter bowls to media temperatures exceeding 125F (52C). The electronic drain unit itself supports up to 190F (88C) media temperature when used with metal bowl filters.

Electrical Data (Solenoid Pilot Valves)

The Series operates at 24 VDC or 110-120 VAC, 50/60 Hz. The solenoid valve energizes to open the drain; the valve returns to closed (NC) when de-energized.

Electrical Connection Options

Certifications & Compliance

Typical Applications & Industries

Machine Control Integration

• FRL filter drain integrated with a machine PLC control system in a 24 VDC installation, with the drain valve wired to a PLC output for timed drain cycles coordinated with machine production schedules and maintenance windows.
• Electronically controlled drain on MD3 or MD4 filter assemblies in automated machinery where drain timing can be adjusted to match compressor duty cycles and condensate production patterns without mechanical drain replacement.
• Multi-drain control systems where several R-DED-24V drain valves are controlled from a single PLC, enabling synchronized drain cycles across all filters in a compressed air system from a central control panel.

High-Moisture Environments

• Full-Size filter assemblies in outdoor or high-humidity installations where condensate production is high and a float drain may not drain frequently enough during peak moisture periods; the programmable interval (as short as 0.5 minutes) accommodates rapid condensate accumulation.
• FRL filters in tropical or coastal facilities where ambient humidity drives high condensate production rates that require frequent, short drain cycles to prevent bowl overflow and moisture carryover.
• Compressed air systems downstream of non-refrigerated air dryers where periodic condensate breakthrough makes frequent automated drain cycles necessary to maintain air quality.

Pharmaceutical and Food Processing

• FRL filter drains in pharmaceutical cleanrooms where timed drain cycles are documented as part of compressed air quality records, providing audit evidence of automatic drain operation intervals.
• Food-grade air preparation systems where electronically controlled drains provide consistent, verified condensate removal cycles with cycle interval data logged by the facility's quality control system.
• Beverage processing lines where 115 VAC drain models integrate with facility PLC controls for automated drain management without dedicated DC power supplies.

Steel and Heavy Industry

• Full-Size and MD4 filter assemblies in steel mills where 24-hour continuous operation makes scheduled electronic drain cycles more reliable than operator-dependent manual draining.
• Compressed air supply systems in foundry environments where high particulate levels can plug float drain valves; the series solenoid valve's positive actuation clears deposits during each timed drain cycle.
• Large-bore FRL filter assemblies at high-volume supply headers where 1/2 inch drain port models (R-DED-115V-4 or R-DED-24V-4) provide large-orifice drain capacity for high condensate discharge volumes.

Ordering and Model Number Configuration

The Series is selected based on three parameters: voltage (24 VDC or 115 VAC), pipe size (1/4, 3/8, or 1/2 inch), and thread type (NPTF or G). Select the model number that matches all three parameters for the specific installation.

Select voltage first: 24V for DC control systems; 115V for AC control systems.

Select pipe size to match the filter bowl drain port thread size: 2 = 1/4 inch, 3 = 3/8 inch, 4 = 1/2 inch.

Add 'W' suffix for G (BSPP) thread; standard model (no suffix) is NPTF thread.

Timer settings (drain time 0.5 to 10 sec; drain interval 0.5 to 45 min) are field-adjustable; no special configuration required at time of order.

Twelve total model variants available: 6 voltage/size combinations per thread type.

For 230 VAC, 50/60 Hz requirements, contact ROSS Controls at (800) 438-7677 for availability.

Accessories

Complete Series Model Number Table

Select based on voltage, pipe size, and thread type.

Related Products & Accessories

• 163 Series External Automatic Drains - Float-operated external automatic drain for Full-Size, High-Capacity, MD3, and MD4 filter bowls - for applications where level-based draining is preferred over timed draining. https://www.rosscontrols.com/en/series/163-full-size-high-capacity-md3-md4
• Full-Size Series FRL Filters - ROSS Full-Size Series filters for 3/8, 1/2, and 3/4 inch port sizes. https://www.rosscontrols.com/en/categories/59-frl-accessories
• MD3 and MD4 Modular FRL Filters - ROSS MD3 (1/4, 3/8, 1/2 inch ports, up to 110 scfm) and MD4 (3/8, 1/2, 3/4 inch ports, up to 230 scfm) modular filter assemblies. https://www.rosscontrols.com/en/categories/59-frl-accessories
• 174 Series Differential Pressure Gauge - Visual indicator for filter element condition monitoring, used alongside automatic drains for complete filter maintenance monitoring. https://www.rosscontrols.com/en/series/174-differential-pressure-gauge
• 173 Series MD3 and MD4 Port Blocks - Male and female end port accessories for MD3 and MD4 modular FRL assemblies. https://www.rosscontrols.com/en/series/173-md3-md4

Frequently Asked Questions (FAQ)

Q: How do I set the drain time and interval on the series?

A: The Series drain timer has two user-adjustable potentiometers on the unit: one for drain time (0.5 to 10 seconds range) and one for drain interval (0.5 to 45 minutes range). Adjustment is made with a small screwdriver at the timer housing. Set the drain time based on the condensate volume in the bowl and the interval based on the condensate production rate of the compressor system.

Q: What voltage options are available?

A: The Series is available in 24 VDC (R-DED-24V series) and 110-120 VAC, 50/60 Hz (R-DED-115V series). For other voltage requirements, contact ROSS Controls at (800) 438-7677.

Q: What is the maximum operating pressure for the series drain?

A: The Series drain valve maximum operating pressure is 230 psig (15.8 bar). The valve body is pressure-rated to 290 psig (20 bar), providing a margin above the typical FRL system operating pressure range.

Q: Is the series compatible with polycarbonate filter bowls?

A: Yes. The Series is compatible with ALL FRL bowl types, including polycarbonate and metal bowls. The drain valve connects to the filter bowl drain port regardless of bowl material.

Q: Can the series be used outdoors?

A: The Series ambient temperature range is 35 to 130F (2 to 54C). For outdoor installations, protect the electronic timer housing from direct weather exposure. The DIN 43650A connector should be used with an appropriate weatherproof cord grip or housing for outdoor applications.

Q: What happens if the drain interval is set too short?

A: If the drain interval is shorter than necessary, the drain valve opens more frequently than required, releasing compressed air each time the drain opens even if no condensate is present. This wastes compressed air and energy. Match the drain interval to the actual condensate production rate by monitoring bowl condensate accumulation at startup.

Q: Can multiple Series drains be wired to the same PLC output?

A: Multiple Series drain valves can share a common power supply, but if they are wired to a single PLC output, they will all drain simultaneously. For independent timing per drain, each should be connected to a separate output or have its own timer module.

Q: Is the series compatible with DIN 43650A electrical connectors?

A: Yes. The Series uses DIN 43650A (ISO 440/6952) electrical connection as standard on all models, compatible with the wide range of standard industrial DIN solenoid connectors available from ROSS and other manufacturers.

Q: What pipe thread standard should I select for international installations?

A: For North American installations using NPT pipe thread fittings, select the standard model (no W suffix). For international installations using G (BSPP) thread fittings, select the W suffix model (e.g., R-DED-115V-3W for 3/8 inch G thread with 115 VAC).

Q: How is the series different from the 163 Series float drain?

A: The 163 Series float drain opens automatically when condensate reaches a trigger level and closes when the bowl empties - it responds to actual condensate level. The Series opens on a programmable timer interval regardless of condensate level. The Series is preferred when consistent timing, machine integration, and documentation of drain cycles are required. The 163 Series is preferred for simpler installations where level-based drainage is sufficient.

Q: What is the minimum drain time setting?

A: The minimum drain time is 0.5 seconds. This shortest setting is appropriate for small filter bowls or low condensate volume situations where a brief drain valve opening expels all accumulated condensate. Longer drain times (up to 10 seconds) are set for larger volume bowls or high condensate systems.

Q: Is technical support available for programming the series timer?

A: Yes. Contact ROSS Controls at (800) 438-7677 for technical support on timer setup, installation, and troubleshooting of the series Electronically Controlled Drain.

Installation & Maintenance Guidelines

• Verify voltage selection (24 VDC or 115 VAC), pipe size (1/4, 3/8, or 1/2 inch), and thread type (NPTF or G) before installation.
• Depressurize the FRL system completely before connecting the series drain to the filter bowl drain port.
• Apply appropriate thread sealant to NPT threads. Do not use sealant on G (BSPP) threads; use a flat face seal or O-ring instead.
• Thread the drain unit into the filter bowl drain port. Tighten to appropriate torque for the thread size.
• Connect the DIN 43650A electrical connector to the drain solenoid. Ensure the connector is properly seated and locked.
• Wire the series to the appropriate power supply (24 VDC or 115 VAC) through the machine control system or a dedicated timer relay.
• Pressurize the system and check all connections for leaks.
• Power the drain unit and verify it opens on the timer cycle by observing condensate discharge or listening for the valve opening.
• Adjust the drain interval potentiometer to the desired interval (0.5 to 45 minutes) and the drain time potentiometer to the desired open duration (0.5 to 10 seconds).
• Ensure the drain outlet is directed to a safe condensate collection point. Do not restrict or block the drain outlet.

Warranty & Global Support

ROSS Controls provides a one-year warranty on all products, covering defects in material and workmanship from date of purchase.

Global technical support available through ROSS offices in the USA, Canada, Brazil, Germany, France, United Kingdom, India, China, and Japan.

Contact ROSS Controls USA at (800) 438-7677 or visit rosscontrols.com for product configuration, technical support, and distributor locator services.

For the complete FRL accessories catalog, dimensional drawings, and installation instructions, visit rosscontrols.com or contact ROSS Controls at (800) 438-7677.

Download Catalog: https://www.rosscontrols.com/en/series/164-electronically-controlled-drains