Learn More: Desiccator Access Frequency
Desiccator Access Frequency
Short Term
A Short-Term Desiccator Storage solution entails frequent access to parts, so Terra recommends including stainless steel door frames to add durability and extend the life of these desiccators. Due to frequent access, the user may also require a fast response time from Terra’s active nitrogen-purging systems to quickly bring the desiccator back to set point conditions (see Terra’s DualPurge and NitroPlex for more information). Also, Individual bleed valves in each chamber will allow moisture to exit before it can migrate to other chambers. Desiccators under this classification can more accurately meet stricter relative humidity requirements; depending on the sensitivity of the parts, a Short-Term Storage solution may best suit the application needs.
Long Term
A Long-Term Desiccator Storage solution entails less frequent access to parts, so stainless steel door frames may be noncritical. Since the doors won’t be opened often, a rigorous gas-purging system may also prove to be noncritical. A single bleed valve for the entire desiccator with multiple chambers may suffice for the application. In this case, a flow meter can be used instead of a smart gas purging controller to manually purge the system in this case.
Cost vs. Control: Terra Desiccators Simplify Your Choice
You need to protect sensitive samples, but you don’t want to overpay. Terra makes product selection as easy as 1-2-3!
1. Critical Control Demands
For applications that require not only a low-RH set point, but a system that recovers it quickly when doors open/close, allows a different set point in each chamber, and/or protects against static and particulate contaminants.
- High access frequency: Doors open/close before system can recover target set point level.
- Low exposure tolerance: Microelectronic or pharmaceutical samples that degrade very quickly when exposed to moisture.
- Exposure testing: Requires a separate %RH monitor/control in each desiccator chamber.
- ESD-sensitive parts: Minute static discharge results in severe degradation, cuts yields.
- Particle Sensitivity: Critical contamination requirements won’t tolerate materials that shed particles or corrode.
No plated or outgassing materials used! - Critical control models use electropolished stainless steel, dissipative PVC and non-adhesive gaskets.
- Stainless Steel Desiccators -
- Adjust-A-Shelf™ Desiccator - Plenum design optimizes gas distribution; Dual Purge/NitroWatch control systems for Low-RH control; chamber-level gas bleeding minimizes moisture migration, improves RH recovery time
- NitroPlex Desiccator - Multiplex RH controller for chamber-level monitor/control and bleeding: results in optimal recovery time for the most sensitive samples
- Ionizing Equipment available for all models above. Also see specialized systems for Semiconductor and Electronics Applications
2. Moderate Control Demands
Sensitive samples may require low humidity set point, but low access frequency minimizes the need for fast RH recovery time.
- Extended Storage/Low Access Frequency: If low humidity is required, fast recovery time is not because doors are rarely opened: you stock the sample and come back for it days or weeks later.
- Dust-Free Conditions: Samples require a clean environment, but chrome plating and adhesive seals are acceptable.
- Moderate Static Protection: Availability of static-dissipative materials a plus, but ionization not required.
- ValuLine SmartDesiccator - These desiccators add an RH display/control module that lets you specify a humidity set point. Since each unit has only one sensor per cabinet, however, large multi-chamber models are not as responsive, and can’t recover a low RH set point, as quickly as Terra’s “Critical Demand” models. Hardware may contain chrome-plated parts or adhesive gaskets.
- Secador 1.0/2.0 Desiccators - These economical systems use desiccant to achieve dry conditions.
3. Minimal Control Demands
You need occasional nitrogen purging or desiccant to bring down the RH, or you may only need a dust-free enclosure without humidity control.
- No Set Point Required: Nitrogen or desiccant maintain low humidity, but control is manual – or unnecessary.
- Dust-Free Conditions: Samples require a clean environment, but chrome plating and adhesive seals are acceptable.
- Moderate Static Protection: Availability of static-dissipative materials a plus, but ionization not required.
- ValuLine ES Desiccator - For occasional nitrogen purging, add a flowmeter and relief/bleed valve. You won't have monitor/control capabilities, but your parts will stay dry! If no RH control is needed, use them as dust-free storage cabinets.
- Portable Desiccator -
- DesiCart - These models are available with a quick-connect fitting for nitrogen purge, but they provide no humidity monitor or automated control.
- Plastic Storage Cabinets - Available in acrylic or polypropylene, these storage cabinets are available with HEPA air showers for enhanced particle control.