Supplemental Manual
High-
IsoDry™ RH Control System
©
Copyright 2017 Terra Universal Inc. All rights reserved • Revised November 2020 • Document No. 1788-26
Terra Universal, Inc. • TerraUniversal.com • 800 S. Raymond Ave. • Fullerton, CA 92831 • TEL: (714) 578-6000 • FAX: (714) 578-6020
9
Add
ADJUST parameter: Use this function to compensate for measured discrepancies between the
NitroWatch %RH readout and that of an independent %RH calibrator. Press the UP/DOWN keys to
adjust the scale up or down. (Default: 0)
This adjustable offset value will wrap around if the maximum or minimum is exceeded. For example, if you
try to set the adjust value above the maximum scale offset of 49.5, the value will wrap around to –50. Also, a
side effect of using an offset value other than zero is that the R/H range will be reduced. For example, if the
offset value is –10, then the maxi um R/H value that can occur is 90 because the input value (100) will be
added to the adjust value before the system uses it.
NOTE
Alr
ALARM time selector, which allows you to specify the alarm scale determined above in either minutes
– LONG – or seconds – SHrt. (default: SHrt)
Press SET again to advance to Normal Run Mode.
Made a mistake?
To reset the system, turn the NitroWatch OFF while in setup mode and restart while holding
the SET button.
2.
Adjust Humidity Set Point:
After completing initial programming, press the SET button to view the current %
RH set point (default setting: 15%). Use the UP/DOWN keys to change this set point. Wait for a couple seconds
without pressing any buttons to save the new set-point.
3.
Beeper Silencing
: Press any front panel button to silence the beeper during an alarm condition.
The NitroWatch will now activate high-flow purging whenever the %RH level inside the desiccator exceeds the
specified set point. Your desiccator is ready for operation.
Installation of at least one Terra Automatic RB Valve (Cat. #1600-60B) is required to protect against
permanent damage to seals and doors
CAUTION
For optimal efficiency of gas delivery and reduced %RH recovery times, Terra recommends factory installation of one
RB valve in each desiccator chamber.
If the Dual Purge System remains at high-level purge, or if it frequently fluctuates between high and low-
level purge, you need to increase your flowmeter setting. Increase the flowmeter setting until the humidity
level falls a few percent below your set point. At this flowmeter setting, the system will be able to maintain
the desired humidity while on the low-level purge—and save nitrogen.
NOTE
Because the humidity sensor is exposed to moisture during shipping, the system must generally operate for
a couple of days in a dry nitrogen environment before the sensor dries out and delivers completely accurate
readings.
NOTE
