What is the LABWIT ZXFD-B5250?

The ZXFD-B5250 is a 250 L bottom-heating forced-air laboratory oven from LABWIT’s ZXFD series.

The oven combines controlled electrical heating with forced air circulation to create a stable heating environment throughout the working chamber.

It is designed for laboratory procedures requiring:

• Drying.
• Controlled heating.
• Thermal conditioning.
• Aging.
• Curing.
• Heat treatment.
• Annealing.
• Stress relieving.
• Burn-in testing.
• Hardening tests.

The 250 L capacity provides considerably more working space than compact benchtop ovens while maintaining programmable temperature control for both routine and more complex thermal procedures.

Key Features of the LABWIT ZXFD-B5250

• 250 L chamber volume.
• Bottom-heating design.
• Forced-air convection.
• Three-dimensional heating system for improved heat distribution.
• Temperature range: ambient +5 °C to 200 °C.
• Temperature accuracy of ±0.1 °C.
• Temperature fluctuation of ±1.0 °C.
• Programmable PID microprocessor control.
• Up to 18 programmable temperature/time steps.
• Large LCD display.
• Digital settings.
• Timer from 0 to 9999 minutes.
• Electro-polished stainless-steel inner chamber.
• Rounded internal corners for easier cleaning and improved air circulation.
• Adjustable stainless-steel shelves.
• Two shelves supplied as standard.
• Maximum capacity of six shelf grids.
• Air-tight door closure system.
• Tempered multi-glazed observation window.
• Adjustable rear air vent.
• 50 mm high-density thermal insulation.
• Over-temperature protection.
• Over-current protection.
• Electrical leakage trip protection.
• Non-volatile memory for retention of programmed parameters.
• Wheel casters for easier positioning.

Forced-Air Convection and Bottom Heating

The ZXFD-B5250 uses a bottom-heating architecture combined with forced-air convection.

Heated air is circulated throughout the chamber to improve heat transfer between the oven atmosphere and the samples.

The combination of forced air circulation and the three-dimensional heating design helps distribute heat throughout the chamber and supports more uniform thermal conditions than would be expected from simple static heating alone.

Why Forced-Air Circulation Matters

In a laboratory drying oven, natural temperature gradients can develop between different locations inside the chamber. Forced-air circulation continuously moves heated air around the samples and shelves.

This helps:

• Improve temperature distribution.
• Reduce localized hot and cold areas.
• Improve heat transfer to samples.
• Provide more consistent conditions across different shelf positions.

The adjustable shelves are also designed to allow air to circulate around the samples during heating.

Precise Temperature Control up to 200 °C

The LABWIT ZXFD-B5250 operates across a temperature range from ambient temperature +5 °C to 200 °C.

The manufacturer specifies:

• Temperature accuracy: ±0.1 °C.
• Temperature fluctuation: ±1.0 °C.
• Temperature uniformity: < ±2.5% at maximum temperature.

A PID microprocessor controller regulates the heating system according to the programmed temperature.

This allows the oven to be used not only for straightforward drying procedures but also for applications where samples must follow defined heating conditions over a specified period.

Programmable Heating Profiles with up to 18 Steps

The ZXFD-B5250 is equipped with programmable temperature control for more complex thermal processes.

The controller can be configured with multiple temperature and time segments, allowing the oven to automatically progress through a predefined sequence.

A typical programmable process may include:

1. Initial heating to a defined temperature.
2. Holding the sample for a programmed time.
3. Increasing the temperature to a second set point.
4. Holding again for another defined period.
5. Continuing through additional programmed stages as required.

The manufacturer specifies programmable control with up to 18 temperature/time steps for the 200 °C oven series.

Large LCD Display

The LCD interface allows operating parameters to be entered and monitored directly on the oven.

Digital control simplifies the setup of:

• Temperature.
• Program stages.
• Heating time.
• Timer settings.

Timer Function

The integrated timer can be programmed from 0 to 9999 minutes, providing flexibility for both short heating procedures and long-duration laboratory processes.

250 L Stainless-Steel Working Chamber

The ZXFD-B5250 provides a spacious 250-liter working chamber with internal dimensions of approximately:

• 600 mm width.
• 535 mm depth.
• 750 mm height.

The inner chamber is manufactured from electro-polished stainless steel.

This construction provides:

• A smooth internal surface.
• Easy routine cleaning.
• Good durability for laboratory use.
• Reduced accumulation of contaminants in difficult-to-clean areas.

Rounded Chamber Corners

The chamber incorporates rounded internal corners rather than sharp internal joints.

This design makes cleaning easier while also supporting smoother air circulation through the chamber.

Adjustable Stainless-Steel Shelves

Two stainless-steel shelf grids are supplied as standard.

The oven can accommodate up to six grids, allowing the internal configuration to be adjusted according to sample size and quantity.

Each shelf measures approximately:

493 × 595 mm

The spacing between grid positions is approximately 105 mm.

Air-Tight Door with Tempered Glass Observation Window

Maintaining a closed heating chamber is important for both temperature stability and energy efficiency.

The ZXFD-B5250 incorporates an air-tight door closure system designed to minimize unnecessary heat loss from the chamber.

Push & Catch Door Mechanism

The door uses LABWIT’s “Push & Catch” closure concept for convenient opening and closing during routine laboratory operation.

Multi-Glazed Tempered Safety Glass

A tempered safety glass observation window allows samples to be visually inspected without opening the oven door.

The 200 °C models use multiple glazing to help:

• Reduce heat loss.
• Improve insulation.
• Allow visual monitoring of samples.
• Reduce unnecessary opening of the chamber.

Adjustable Air Vent for Moisture Removal

Drying processes frequently release moisture or vapors from the sample into the oven chamber.

The ZXFD-B5250 therefore incorporates an adjustable air vent located on the rear wall.

The airflow opening can be adjusted using a control knob positioned on the side of the oven.

This allows operators to regulate the discharge of humidity generated during drying and heating procedures.

50 mm High-Density Thermal Insulation

The oven incorporates approximately 50 mm of high-density insulation around the working chamber.

The insulation helps reduce heat dissipation to the surrounding laboratory environment and improves the thermal efficiency of the oven.

Combined with the air-tight door and insulated observation window, this helps maintain the internal heating conditions while limiting unnecessary heat loss.

Integrated Safety and Protection Functions

Laboratory heating equipment may operate at elevated temperatures for extended periods, making safety monitoring an important consideration.

The LABWIT ZXFD-B5250 includes multiple protection functions.

Over-Temperature Protection

An over-temperature limit protection system helps protect the oven and samples if abnormal heating conditions occur.

Over-Current Protection

Separate over-current fuses provide electrical protection against excessive current conditions.

Electrical Leakage Protection

A trip-switching protection system is incorporated for electrical leakage conditions.

Alarm Function

The controller includes alarm functionality to alert the operator when abnormal operating conditions are detected.

Non-Volatile Memory

The oven stores programmed operating parameters in non-volatile memory.

If electrical power is interrupted, the previously configured parameters are retained rather than being lost.

Wheel Casters for Easier Installation and Positioning

Because the ZXFD-B5250 has a chamber capacity of 250 L and a net weight of approximately 108 kg, moving the oven manually would otherwise be inconvenient.

LABWIT supplies wheel casters as standard for oven models with capacities of 210 L and above.

This makes installation, repositioning and access for laboratory cleaning or maintenance more convenient.

Applications of the LABWIT ZXFD-B5250

The ZXFD-B5250 is designed for routine drying as well as controlled laboratory heating applications.

Typical applications include:

• Laboratory glassware drying.
• General sample drying.
• Controlled thermal treatment.
• Aging tests.
• Bonding processes.
• Curing.
• Heat treatment.
• Annealing.
• Stress relieving.
• Burn-in testing.
• Hardening tests.
• Material conditioning.
• Research and quality-control laboratories.

Glassware and Laboratory Material Drying

The combination of temperatures up to 200 °C and forced-air circulation makes the oven suitable for routine drying of laboratory glassware and compatible laboratory materials.

Material Testing and Conditioning

The programmable temperature controller can be useful for materials that need to be exposed to controlled heating stages for aging, curing or other temperature-dependent processes.

Quality-Control Laboratories

The 250 L capacity makes the system suitable for laboratories that need to process multiple samples or larger objects within the same controlled heating cycle.

LABWIT ZXFD-B5250 Technical Specifications

Specifications are based on current manufacturer information and may be subject to change.

Why Choose the LABWIT ZXFD-B5250?

When Should You Consider the ZXFD-B5250?

The LABWIT ZXFD-B5250 is particularly suitable when a laboratory requires:

• A forced-air drying oven with approximately 250 L capacity.
• Operating temperatures up to 200 °C.
• Programmable multi-stage temperature profiles.
• Uniform forced-air heating.
• A stainless-steel working chamber.
• Flexible shelf positions for different sample sizes.
• A window for visual monitoring.
• Controlled removal of moisture from the chamber.
• Routine drying as well as controlled thermal treatment.

For processes requiring temperatures above 200 °C or specialized atmospheric control, a different oven configuration should be selected according to the application requirements.

Frequently Asked Questions About the LABWIT ZXFD-B5250