Glass Door Humidity Chambers

The Bemco FW30, mechanically cooled, Glass Door Humidity Chamber has a temperature range of -18 C to +94 C (0 F to 200 F) and a humidity range of up to 5% RH to 95% RH (see the Chart below). This chamber features dry air injection and a direct humidity sensor. It operates without dewpoint limit from 5% RH to 95% RH over the range of 30 C to 85 C and even allows operation at 20% RH at 5 C and 50% RH at -14 C!

Based on the pioneering Bemco KDR Series of Glass Front Burn-in the Temperature Cycling Chambers these systems can be loaded with large solid objects normally tested in walk-in chambers. A view of the entire workspace lets you see your test objects operate and keep track of products.

The FW30 accepts shelves and can easily be adapted for use with card cages, product carriers, and production fixturing.

Clear door access height is 63 inches and clear access width is 27 inches due to the door frame.

---

Conditioning

Chamber air is recirculated by a high volume, stainless steel axial fan discharging through a hinged right side mounted guard and diffuser baffle to create a uniform environment around your test objects.

The fan is driven by a horizontally mounted motor with dual ball bearing races, connected by a large diameter extended stainless steel shaft.

A proportionally controlled single compressor refrigeration system utilizing a modern environmentally friendly refrigerant cools the workspace. The system includes automatic hot gas bypass and suction cooling unloading. Fast-response open type heaters, located behind a radiation baffle, raise chamber temperature as required.

Chamber humidity is increased by a Bemco mass transfer vapor generator with a sight glass, a low water cutoff, and automatic drain freeze protection. The vapor generator can be shutoff and drained when very low humidity control is desired.

Chamber humidity is decreased by the direct injection of -73 C (-100 F) dew point dry air produced by a dual bed regenerative compressed air drier furnished with an isolation valve, an inlet particulate and coalescing filter and an outlet filter regulator.

Water and air connections are located on the top.

---

Safety Systems and Electrical Wiring

All systems have thermal and current sensors on the compressor, charging valves, and a sight glass as well as numerous safety and reliability protection systems for dependable operation. All electrical wiring meets the United States National Electric Code. UL and CSA approved components are used where possible.

An FW30 left side view is shown at the left. Notice the access port for convenient access to the chamber workspace. Additional access ports or fixturing can easily be located in this wall or on the chamber rear wall making this system ideal for electronic testing where large numbers of penetrations for wiring are required.

---

Construction

The FW30 has a sloped roof and a sloped floor to minimize dripping on test objects and to meet Mil-Std 810 and Mil-Std 202.

It includes a continuously heliarc welded 304 Series stainless steel liner with high temperature fiberglass insulation. No asbestos is used in chamber construction. The outer case is fabricated from cold rolled steel finished in Bemco Blue.

A matching machinery housing is mounted on the right hand side. The FW30 has a very large workspace for its extremely compact size.

---

Controls

The FW30 is furnished with a two channel, microprocessor based, programmable 1/4-DIN, solid state, 256-step ramping controller which includes a 4-line LCD interface display, and a large red LED display.

Temperature inside the chamber is sensed by a precision thermocouple.

Humidity is sensed by a direct reading electronic humidity sensor accurate to + or - 2% RH over the dew point temperature range of minus 20 C to 85 C (-4 F to 185 F). This sensor is mounted through a sleeve located on the roof near the left side of the door.

---

Performance

Cooling rate from 75 C to -15 C in less than 90 minutes. Heating rate -15 C to 75 C in less than 60 minutes. Both with the chamber empty.

+ or - 1 C (+ or - 1.8 F) guaranteed control, + or - 0.15 C (+ or - 0.25 F) typical.

Humidity 5% RH to 95% RH, see chart. 95% RH at 85 C (185 F) maximum.

---

Optional Equipment

• Access Ports. Sizes are 2”, 3”, 4” and 6.” One 3” access port in the left wall is provided with each chamber.
• A 5-gallon water reservoir with an internal pump, low level sensor, low level alarm, and an isolation valve to allow system operation without a source of pressurized water. The tank requires occasional manual filling.
• A single cartridge, demineralization system that produces up to 4 liters / minute of water. The demineralization system Includes a water purity indicator.
• Casters, two swivel and two fixed.
• Shelf pilasters and wire-type stainless steel shelves.
• GN2 gas purge with pressure regulator, gauge, flow measuring and regulating valved rotameter, and vent.
• Two refrigeration gauges mounted in the refrigeration compartment with or without isolation valves.

---

Optional Instruments

Available instrument options include:

• Microprocessor-based, FM Approved, high over-temperature safety control.
• Set of two, one high and one low microprocessor-based, FM Approved temperature safety controls.
• Remote control over an Ethernet Link.
• 12-inch, two pen, chart printing, circular recorder.
• Pre-fixtured relay racks for mounting test items.
• Strip chart recorder.
• See Bemco Instrument Bulletin for further descriptions.

---

Available Literature Includes:

Bemco FW30 Series, Glass Door Temperature/Humidity Chambers. Document is triple fold front and back, 2 pages, 353 KB download.

---

The systems described above are our Standard Models. We make custom equipment to your specifications.  If you have any questions, need assistance in preparing a specification, or have a technical problem you want help with, we are ready.  Our quotations and advice are free.