CSZ MICRO-TEMP LT 749 - Required Accessories; Functional Description of the Micro-Temp Lt System; 1-5.1. Theory of Operation; 1-5.2. Heating System

INTRODUCTION MICRO-TEMP
®
LT, Model 749
OPERATION AND TECHNICAL MANUAL
Page 18 of 75
1-4. REQUIRED ACCESSORIES
The only essential accessory for the MICRO-TEMP
®
LT unit is a thermal pad. They are available in
a variety of sizes. The maximum thermal pad allowed for the MICRO-TEMP
®
LT is 25” x 19”.
The thermal pad is connected to the unit via the permanently attached eight foot (2.4 meter) hose
with “quick-connect” couplings, featuring automatic shut-offs on the end of each hose. The
automatic shut off pertains to the hose only, and therefore the clamp for the blankets/pads must be
shut to avoid water leakage.
A list of MICRO-TEMP
®
LT System Equipment and accessories are found in Figure (6-8).
1-5. FUNCTIONAL DESCRIPTION OF THE MICRO-TEMP
®
LT SYSTEM
1-5.1. THEORY OF OPERATION
The MICRO-TEMP
®
LT System utilizes a linear temperature controller featuring a digital read-out
of water and set point temperature (selectable to indicate Celsius or Fahrenheit for 100V and
115V only), and operates between a temperature range of 20°C to 42°C (68°F to 107°F). In
addition, this model includes audible indicators and visual indicators for power failure and warning
indicators, along with a visual indicator for low water. Safety features include: linear control to
ensure accuracy of temperature setting at all times by eliminating the need for calibration; digital
display of actual water temperature as well as set point temperature; a low water cut-off switch
which shuts off both the heater and circulating pump; an independent high limit sensor to guard
against possible over-heating and subsequent patient injury; and a tilt switch indicator which
sounds and shuts the unit off when tilted more than approximately 20° in any direction from the
horizontal plane.
1-5.2. HEATING SYSTEM
The MICRO-TEMP
®
LT heating system consists of an immersion heater, a water temperature
control, and two high temperature safety devices. Temperature ranges of the system are described
in Section (1-6.4). The immersion heater is located in the reservoir. The water circulating in the
reservoir flows around the immersion heater and is warmed by conductive heat transfer.
The heating system is operational whenever the control system calls for an increase in the
temperature of the circulating water. It is important to note that the rate of change in the circulating
water temperature is not directly proportional to the rate of change in the temperature of the patient.
1-5.3. CIRCULATING SYSTEM
The MICRO-TEMP
®
LT circulating water system is composed of a magnetically driven circulating
pump, a single self-contained reservoir, a connecting hose, quick-disconnect fittings, and a localized
heat therapy pad.
The 0.24-gallon (0.9 liters) capacity reservoir is composed of a single circulating unit.