Installation Instructions 35mm RS Mount VR2X-RSM
The VR2X-RSM is a fully assembled compact mounting solution for the RS Series dehumidifier membranes in enclosures up to five litres. The 35mm barrel mounting integrates both a RS1 membrane dehumidifier and VREG2 power supply within single housing. It includes a locking ring for ease of installation, and you only need to add a standard 15W USB-C power supply.
VREG Power Adapter Board
VREG2 Power adapter boaed
The VREG2 power adapter board integrated within the VR2X-RSM reduces the 5V DC supplued from a standard USB charger to the current limited 3V DC needed by the dehumidifier
VREG2 Technical Information
Fold-Back Current Limiting
The dehumidifier membranes can absorb humidity if no supply voltage is present. This moisture needs to be discharged on startup and can lead to a higher inrush-current than the regular operating current. During startup the supply voltage should not fall below 2V, otherwise moisture discharge is not possible or significantly delayed. The use of fold-back current limiting regulates the output current to maintain the required minimum supply voltage for the dehumidifier membranes.
The RT9059 voltage regulator used on the USB-C-VREG2 contains an independent current limit and the short circuit current protection to prevent unexpected applications. The current limit monitors and controls the pass transistor’s gate voltage, limiting the output current to 3.1 A (typical). When the output voltage is less than 0.2v, the short circuit current protection starts the current fold back function and maintains the loading current at maximum 1.8A. The output can be shorted to ground indefinitely without damage.
Technical Parameters
VREG 2, VRS-300, VRD300
| Symbol | Parameter | Condition | Min | Typical | Max | Units |
| VIN | Input voltage | USB-C | 3.3 | 5 | 5.5 | V |
| VOUT | Output Voltage | 3.0 | V | |||
| IOUT | Output current [1] | Rated | 3000 | mA | ||
| Output accuracy | 85°C | 1.5% | ||||
| IQ | Quiescent current | 0.6 | mA | |||
| Current limiting | Fold-back | |||||
| T | Operating temp. | -40° | +85° | C | ||
| Dimensions | 25 x 16 x 4 | mm |
Note
[1]: The voltage regulator of the USB-C-VREG2 is specified for a rated output current of 3000mA. However, with a 5V USB-C supply voltage this leads to a thermal power dissipation of 6W. Continuous operation at 3000mA would hence require cooling. The intended application of the USB-C-VREG2 is with a Rosahl M-series dehumidifier membrane e.g., M-1J1R, M-2J1R, M-3M1R, M-3J1R and MDL-3 which draw high inrush.
USB Power Supply
The VREG-2 is not an official USB-C PD (Power Delivery) sink device and may not be recognised by some PD or special purpose USB-C power supplies. In the event of a problem, try it with a standard 15W USB power supply.
Cautions:
Prior to mounting in an enclosure, the VREG2 power adapter boards may be damaged by electro-static discharge (ESD) and should be handled appropriately trained personnel.
The VREG2 should not be operated without protection circuitry if connections to the product’s pin header rows are longer than 3m.
Manufacturer in the European Union
Declaration of RoHS available
Declaration of REACH Directive available
Version 2.2
Westside-International Ltd
Boston House, Downsview Road, Wantage, Oxfordshire, OX12 9FF. UK