Taylor-Wharton Low Level Alarm User Manual

TW-307 B

LOW LEVEL
ALARM

The Cryo-Sentry is an optional accessory for se­lected models of portable liquid nitrogen refrigera­tors. It is designed to provide visual and audible
alarms when the liquid nitrogen level drops below a
preset level, usuaully 25 percent of the container
capacity. This monitoring system provides a high
level of security, alerting the user to low nitrogen
levels, and serves as a reminder for scheduled
refilling.

Safety

The Cryo-Sentry consists of three components: Alarm
Module, Power Supply, and Sensorcore.

Before using this accessory, read the Handle with Care
booklet (TW-10) provided with the unit. It details safety
precautions that must be read and understood before
using the equipment.

Following are a few precautions described in Handle
with Care. Please be sure to read the entire booklet.

Do not touch liquid or cold metal surfaces with
your bare skin. The liquid nitrogen used in cryogenic

refrigerators is extremely cold: -320°F (-196°C).
Exposure of skin or eyes to liquid, cold gas, or frosted
parts could result in a severe, frostbite-like injury.

Use only the sensorcore provided with this acces­sory or the one originally shipped with the refrig­erator. A tight-fitting plug or stopper will cause a

pressure increase in the container that may damage
the container and/or cause personal injury.

For Liquid Nitrogen
Refrigerators

Installation

The Cryo-Storage low level alert arrives ready for
immediate use.

110 VAC Power

The alarm runs on either 110 VAC or 4 AA size battery
power. For 110 VAC, simply plug the wall transformer
into alarm module at the jack labeled “AC POWER”.
Next, plug the sensorcore into the alarm module at the
jack labeled “SENSOR”. (The Cryo-Sentry can either
be attached to your dewar with the VELCRO® strips
provided or can be mounted to the wall.) Lower the
sensorcore into the refrigerator, and plug the trans­former into a 110 VAC outlet or a surge protected
power supply.

Battery Power

The alarm can also run on four (4) AA batteries. Once
installed, the batteries will supply power to the monitor
for an extended period of time.

To install the batteries, remove the back cover and
insert the batteries. The positive (+) terminal should be
pointed towards the “+” label on the battery holder.

Installation (cont.)

Remote Alert

Duration of battery-powered operation can vary from
six months to one year depending on the usage. An
audible and visual alert will be activated once battery
power is low.

Operation

The Cryo-Storage low level alert automatically checks
the liquid level every 30 minutes. This conserves
battery power thereby extended the security. The 25
percent level notification provides sufficient time for the
user to refill the dewar.

The user can check the level without opening the
vessel by pressing the “LEVEL CHECK” button. Re­sults will be displayed in 30 seconds. The possible
results are provided in the following table:

Conditions Color

Level Ok Green 30 sec. No
Checking Yellow 1 sec. No
Low Battery Red 1 sec Yes
Low LN(2) Red 2 sec. Yes
Sensor Fault Red 3 sec. Yes

 MUTE: The user can mute the audible

alarm at any time by pressing the “TEST/
MUTE” button. The alarm will remain muted
until the next 30 minute check is made.
However, the LED will remain red until the
LN2 level is raised above 25 percent.

 TEST: The status light and the audible horn

can be tested by depressing the “TEST/
MUTE” button. This test can only be made
so long as an alert condition does not exist.

Flash

Rate

Audible

The remote alert circuit is activated immediatley once
a Low Battery, Low LN
The remote alert will remain active even if the battery
power is depleted. Pins 1 and 2 are closed in normal
operation. Pins 2 and 3 are closed during a remote
alert condition.

Remote Alarm Plug Connection

or Sensor Fault is detected.

2

Replacement Parts

Description Part Number

Alarm Module…………………………………..5140-1124
Power Supply ………………………………….5190-3094
Remote Alarm Plug ………………………….R06K-8C20
Sensorcore Assembly for 18XT,20XT, or 34XT

.......................................................................R033-8C40

Sensorcore Assembly for 34HC …………....R034-8C40

Sensorcore Assembly for 35HC …………....R037-8C40

Sensorcore Assembly for 35VHC ………….R036-8C40
Sensorcore Assembly for 1575RS ………...RS15-8C40
Sensorcore Assembly for 3000RS ………...RS30-9C16

Sensorcore Assembly for 4800RS …….......R05K-8C27

Sensorcore Assembly for 3K …………..…...R03K-8C49
Ordering Information – Order all replacement parts

and accessories from your supplier or from Taylor­Wharton at the addresses listed below. Please include
the part number, quantity, and description of each part
requested.

Taylor-Wharton

4075 Hamilton Blvd.
Theodore, AL 36590
Phone: [phone]
(800) TW TANKS (898-2657)
Fax: [phone]