Twite Instruments TD-196 User manual

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
TWITE INSTRUMENTS PTY. LTD. ®
A.C.N. 050 199 758
No. 3 STANLEY St. MOOROOPNA VICTORIA AUSTRALIA 3629.
PO. Box 176 SHEPPARTON VICTORIA AUSTRALIA 3630.
Telephone [phone] FAX [phone]

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
© Copyright 1994 - 1999 Twite Instruments Pty. Ltd. All rights reserved.
No part of this publication may be reproduced, translated into another language,
stored in a retrieval system, or transmitted, in any form or by any means, electronic,
mechanical, photocopying, or otherwise without the prior written consent of
TWITE INSTRUMENTS Pty. Ltd.
Every precaution has been taken in the preparation of this publication.
TWITE INSTRUMENTS assumes no responsibility for errors or omissions. Neither
is any liability assumed for damages resulting from the use of the information
contained herein.
Specifications of the THERMOSTAT Model TD-196 are subject to change without
notice.
Twite Instruments Pty. Ltd. or any of its Partners, Principals or Employees cannot be
held responsible or liable for any loss of product, produce or buildings where any of
Twite Instruments Pty. Ltd. Products are found to be responsible for the loss of any
product, produce or buildings.
IBM ® is a trade mark of International Business Machines.
EPSON ® is a trade mark of EPSON.
WINDOWS & WINDOWS 3 ® is a trade mark of Microsoft.

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
CONTENTS
INSTALLATION
MOUNTING 6
POWER & SOLENOID CONNECTION 6
SENSOR INPUT CONNECTIONS 7
SENSOR POSITIONING 8
PRINTER CONNECTION (RS485) 8
ALARM OUTPUTS 9
DISPLAY CONTRAST ADJUST 33
DISPLAY FUNCTIONS
DISPLAY LED 10
SETTING LED 10
D/M/S LED 11
REFRIG LED 12
SUCTION LED 12
FANS LED 12
ALARM LED 12
KEYBOARD FUNCTIONS
"SET" KEY 12
"ENT" KEY 13
" s" "DIS" (up arrow) KEY 13
" t" "DIS" (down arrow) KEY 13
PASSWORD
USING PASSWORD 14
CHANGE PASSWORD 14
PASSWORD UNKNOWN 14
SELECTING CHANNELS 15
FUNCTION NUMBERS 16

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
CONTENTS
SET POINT PARAMETERS
TEMPERATURE 17
DIFFERENTIAL 18
SET POINT USAGE TIMES 18
HIGH ALARM TEMPERATURE SET POINTS 19
LOW ALARM TEMPERATURE SET POINTS 19
HIGH ALARM DELAY SET POINT 20
LOW ALARM DELAY SET POINT 20
SET DEFROSTS 21-22
DEFROST AUTO OFF 23
DEFROST MANUAL ON OFF 23
CONTROL ON OFF 24
FANS CONTINUOUS AUTOMATIC 24
HIGH ALARM ACTIVE (OVERRIDE) 25
LOW ALARM ACTIVE (OVERRIDE) 25
DIFFERENTIAL TYPE 26
POWER ON DELAY 27
UNIT NUMBER 27
COOLING OR HEATING 28
SET REAL TIME CLOCK 28
CALIBRATE REAL TIME CLOCK 29
PRINT 29-30
DATA LOGGING 31
PASSWORD ON OFF 32
CHANGE PASSWORD 32
PUMP DOWN SET POINT 33
DISPLAY INTENSITY 33
DAILY SET POINTS 34
LINE FEED YES NO 35
CHANNELS CONNECTED 35
CHANNELS TO SCAN 36
SCAN TIME 36
SCAN YES NO 36
CONTROL CHANNEL 37
RESET MAXIMUM MINIMUM 37
BAUD RATE SET 38
LONG TERM OR PULL DOWN MODE SET 38
CALIBRATION VALUES 62

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
CONTENTS
PRINTER COMMUNICATIONS 40
CALIBRATING AND DEFAULT VALUES :-
CALIBRATION BUTTON ACCESS HOLE 42
CALIBRATE VALUES CHECK & ALTER 43-44
CALIBRATION VALUES UPDATE 44
TEST DISPLAYS 44
MEMORY (RAM) TEST 44
RESET DATA LOGGING 45
RESET PASSWORD 45
SET PARAMETERS TO A DEFAULT VALUE 45
KICK START REAL TIME CLOCK 45
CALIBRATE SENSORS 446-47
START UP DEFAULTS VALUES 47
SPECIFICATIONS 48-50
ERROR MESSAGES 51-52
REMOTE DISPLAY MODULE
MOUNTING 53
POWER SUPPLY 53
RS485 INPUT 54
PARALLEL OUTPUT 54
DISPLAY 54
KEYBOARD 55
FUNCTION NUMBERS 56
SETTING FUNCTIONS
SCAN TIME 56
SCAN YES or NO 56
SCAN UNITS YES or NO 57
SCAN CHANNELS YES or NO 58
DISPLAY INTENSITY 58
BAUD RATE 59
ERROR MESSAGE 59
DEFAULT VALUES 60
RESET 61
INTERNAL CONNECTIONS 61

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
INSTALLATION
MOUNTING.
The unit should be mounted at eye level for easy viewing and access to keyboard,
using the fixing screws provided. Ensure it is in a dry area and not in direct sunlight.
POWER & SOLENOID CONNECTION.
Power to the main unit must be 240 V a.c. 50 Hz and connected to the terminals
marked A. N. E. The EARTH must be connected to the E terminal. The shield of
the sensor cable must also be connected to the earth terminal.
The supply must be a direct line from the main switch board and not an exten-
sion of other power points etc. AND MUST BE OF THE SAME PHASE AS
THE CONROL POWER SUPPLY

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
INSTALLATION CONT..
SENSOR INPUT CONNECTIONS.
Sensor cables must be of the SHEILDED type and must not exceed 500 Metres.
Sensor cables should not run parallel or in the same duct as high voltage cables.
The shield of the sensor cable must be connected to the EARTH terminal and must
only be connected at one end, the shield must be continuous at each sensor drop.
Sensors require one wire for common (usually red) and one for positive (usually
black).
If more than one sensor is used (optional extra). The common (usually red) may be
tied to one wire which can be connected to all sensor commons. i.e.. for 8 sensors 9
wires need only be used.
The sensors (if a single sensor is used) negative wire (usually black) must be con-
nected to terminal SEN - and the positive wire (usually red) to SEN +.
Extra sensors (optional extra) positive wire (usually red) must be connected to
terminal SEN + and the negative wire (usually black) must be connected to its
corresponding channel number marked INPUTS 2 to 8 inclusive.
Sensors are numbered before shipment and are calibrated at the factory. Therefore
each sensor’s negative wire (usually black) must be connected to its’ corresponding
sensor input. For instructions on how to re calibrate sensors see CALIBRATE
SENSORS.

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
INSTALLATION CONT.
SENSOR POSITIONING.
The sensor (and extra sensors, optional extra) may be placed in any convenient
position keeping in mind that if more than one sensor was set to be used for control-
ling, the average of those sensors will the temperature used for control and will be
the temperature displayed in the normal (not scan mode) display mode while display-
ing the temperature.
The sensor or sensors used for control should be placed in the return air section for
cooling, and where applicable for heating.
The distance a sensor may be placed from the unit should not exceed 500 meters
The sensors must not be exposed to temperatures below -50.0 oC or above
+150.0 oC
Sensors and cables should not be fully immersed in any liquid for long periods of
time. They may be immersed for short periods for calibration purposes only. The
stainless steel sheath may be immersed in a liquid that will not corrode AISI 304
Stainless Steel.
PRINTER CONNECTION (RS485).
Up to 16 units (TD-196) can be connected to a printer (a standard EPSON ® or
compatible printer with a SERIAL interface) for printing out of temperatures at
preset times, data logged temperatures and parameter set points.
All units in the chain must have their RS485 - terminals connected
together (in parallel) and their RS485 + terminals connected together (in parallel)
using single twisted pair coaxial cable. The shield must be connected to GROUND at
one end only (not at each unit).
To connect to a printer with an RS232 port, the TD-196's + serial
output must be connected to the rs232 receive input (pin 3 on the 25 pin D connec-
tor) and the ground output/input on the TD-196 connected to the signal ground of the
printer (pin 7 on the 25 pin D connector). The pins 4 & 5 on the 25 pin D connector
must be tied (shorted) together. This type of communication is only available if all
TD-196 units are in close proximity to each other and the printer, (no more than 6
metres).
For longer distances and parrallel interface see later under Printer Communications
and Remote Display Module

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
INSTALLATION CONT.
ALARM OUTPUTS.
The alarm outputs (ALM terminals) are dry relay outputs which may be connected to
an external voltage source.
The relay is activated (energized) when the alarm is off, allowing an external alarm
(if it has a battery backup connected) to sound if the unit loses power.
The contact rating of the relay is 24 V d.c. 1 A.

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
DISPLAY FUNCTIONS
LED DISPLAY.
Used to display all parameters and set points etc.
1. 4 Digit Led display to display temps and all other set points etc.
2. Display LED (without the D/M/S LED lit) To display one of the D/M/S
functions press the "ENT" key, then press the s "DIS" key while
holding the "ENT" key pressed, the unit will light the D/M/S LED in
rotation, either off (this function), permanently on (for scan mode), fast
flash (maximum/minimum) or slow flash (data log display).
NOTE :- If the 8 channel option is not present the Display will indicate "Errr".
The following is if the D/M/S LED is not lit, see next page for functions
with the D/M/S LED lit :-
Indicates that one of the following is displayed depending on the LED
display on the right. To change to a different display Press the
s t "DIS" Keys.
1. Current Control temperature. The temperature
used for control, which is dependant on channels
set in CONTROL CHANNEL (Set Point No. 33)
and may be any channel or the average of selected
channels. (channel 1 only if 8 channel multiplexer
is not present).
2. The current temperature set point.
3. The current Differential setting.
4. The High Alarm temperature set point (chan 1).
5. The Low Alarm temperature set point (chan 1).
6. The current Set Point number (1 - 4) (chan 1).
7. The current time in HRS. MIN. (24 hour format).
8. The current Day & Date (day 1 = Sunday).
3. Setting LED :-
Indicates that the unit is in setting mode.

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
DISPLAY FUNCTIONS CONT.
LED DISPLAY CONT.
4. D/M/S LED (PRESS & HOLD THE "ENT" Key, THEN PRESS THE s
"DIS" Key with the display LED lit to cycle through these or
normal displays) :-
If OFF the display is as the previous page.
If ON continuously, the unit is in the SCAN mode. This is only available if the 8
channel option is present. The unit will scan (if the set point SCAN YES NO is set to
YES) all channels temperature, alarm set points or the current set point used (others
are for the control channel only and will not scan) as indicated by the right hand
LED on entering this mode (temps of individual sensors, not averaged first.). By
pressing the s t"DIS" Keys the unit will cycle through the channels that are set
to yes for CONNECTED, To check which parameter is displayed press the "ENT",
(the right hand LED will indicate which parameter is being displayed). To change
which parameter is displayed press the "ENT" key and hold on until the parameter
indicator LED (right hand LED'S) change from TEMP to HI/AL, LO/AL, ST/No
(cycles through each display parameter at 2 second intervals approx.). When the
desired parameter to be displayed on the right hand LED'S release the "ENT" key,
that parameter will then be displayed in the SCAN mode.
If flashing fast it is displaying Maximum / Minimum temperatures. The first to
display is the maximum (time) of channel 1. To change channels to display press the
s "DIS" key and press the t "DIS" key to toggle from maximum to the minimum
to be displayed (the decimal point will lit on digit "0", right hand digit to indicate
that the maximum time/temperature is shown). To show the HOUR:DATE of when
it happened press the "ENT" key (decimal point flashes to indicate time), press the
"ENT" key again to display the maximum/minimum temperature again.
If flashing slowly it is displaying Data Logged temperatures. The first to display is
the temperature of channel 1 (or the lowest numbered channel that was set in SET
DATA LOGGED) at the last time it was logged. To change the time of data that was
logged press the s t "DIS" keys, the display will roll around in a circular mode
displaying the data that was logged for the selected channel. To change to another
channel to display press the "ENT" key, if the channel was set to none (no data
logged) it will skip to the next channel to display.
To toggle from displaying the TEMPERATURE to HOUR:DATE press & hold the
"ENT" key Then press the t "DIS" key.

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
DISPLAY FUNCTIONS CONT.
LED DISPLAY CONT.
5. REFRIG LED (control 4) :-
Indicates that the Refrigeration (Liquid or output 4) Solenoid is on.
6. SUCTION LED (control 3) :-
Indicates that the Refrigeration (Suction or output 3 ) Solenoid is on.
7. FANS LED (control 1) :-
Indicates that the Refrigeration (fans or control 1) Solenoid is on.
8. DEFROST (control 2) :-
Indicates that the defrost (defrost or control 2) Solenoid is on.
9. ALARM LED (flashing) :-
Indicates that the ALARM is on (active). ALARM relay off..
KEY BOARD FUNCTIONS
SET KEY.
Pressing the "SET" key activates the Setting mode. If the PASSWORD is
active (password set to ON, Function No. 23), see the pass word section on page 14.
If the Password is not active (password set to OFF, Function No. 23). Then
press the s t Keys to go to the required set point to change. The set point
numbers are displayed on the 4 digit LED display. See SET POINT NUMBERS for
a listing.
When the correct set point number is displayed press the "ENT" key to select
that function. If the 8 channel option is present, some functions will require
channel selection, see SELECTING CHANNELS on page 15.
If the 8 channel option is not present, the value displayed after pressing the
"ENT" key will be the last value of that set point.

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
KEY BOARD FUNCTIONS CONT.
SET KEY CONT.
If more than one value is required (i.e. the 4 or 12 set points for control of cooling
or heating respectively, defrost and time etc.) the unit will request each value in turn
to be altered. After each value has been entered press the “ENT” key. The right hand
LEDS will descend to the next number showing which set point number is being set
at that time. With defrost the number 8 LED will remain lit for the first start time and
the number 1 LED will also be lit showing that the first defrost time is being set.
When setting time 8, only the number 8 LED will be lit. To have less that 8 defrosts
in one 24 hour period set the remaining start times to the same start time as the last
required defrost in that day. The unit will automatically reset the start time of the
next defrost start time to the start time of the previously set start time. After all
required values have been altered (or checked), the displays will revert to normal run
mode after the last "ENT" key press.
ENT KEY.
This key is used to enter the value selected into memory and other functions
as described. The memory will retain all set point values and data logged etc. for at
least 10 years with the power off.
sUP (DIS) KEY.
This key is used to increase the value while changing set points and to select a
channel while in the set mode and channel selection is required (optional extra) and
to change to the next display while in normal run mode and other functions as
described..
tDOWN (DIS) KEY.
This key is used to decrease the value while changing set points and to select
a channel while in the set mode and channel selection is required (optional extra) and
to change to the last display while in normal run mode & other functions as de-
scribed..
NOTE:- HOLDING THE sor t KEYS DOWN WILL INCREASE OR
DECREASE THE VALUE FASTER ON SOME FUNCTIONS.

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
KEY BOARD FUNCTIONS CONT..
PASSWORD
USING PASSWORD.
(use SET, ENT, sand tkeys)
When the password is required (PASSWORD ON, function 23) the unit will request
the password when the “SET” key is pressed with the following Display.
The PASSWORD consists of 4 numbers between 0 to 9 inclusive.
To enter the first number press the "s" or "t" keys until the first number of the
password chosen is displayed, then press the “ENT” key. The display will show a 0
and the right hand LEDS will light the No. 2 led to show that the second number is
to be entered. Repeat as for the first number until all 4 numbers have been entered. If
the correct password was entered the display will show one of the functions that may
be altered, the "s" or "t" keys may be then pressed to choose the required function.
If the wrong password was entered, the display will show the following and then
revert to that which was originally displayed before any of the above keys were
pressed.
CHANGING THE PASSWORD.
The password cannot be changed (Function No. 24) if the password is not
active. To change the password, first make sure that the password is active in func-
tion No. 23. See the following individual function set point change for a full descrip-
tion on how to use these functions.
PASSWORD UNKNOWN.
See PASSWORD RESET in CALIBRATING AND DEFAULT VALUES.

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
KEYBOARD FUNCTIONS CONT..
SELECTING CHANNELS (8 CHANNEL OPTIONAL EXTRA).
FUNCTIONS THAT REQUIRE CHANNEL SELECTION ARE INDIVIDUAL FOR
EACH CHANNEL PROVIDING THAT THE 8 CHANNEL OPTION IS PRESENT.
WHEN CHANNEL SELECTION IS REQUIRED THE FOLLOWING DISPLAY
WILL BE SHOWN AFTER THE FUNCTION (TO SET) HAS BEEN SELECTED
(PRESSING THE "ENT" KEY FOR THE FIRST TIME (AFTER THE PASS-
WORD HAS BEEN ENTERED IF REQUIRED).
To select a different channel than channel 1 press the skey, when the correct
channel is displayed (LED on that channel flashes), press the tkey. When the t
key is pressed the D/M/S (green LED) will turn on to indicate that it was selected
and off to indicate that it is not selected, To select more channels or to de select a
channel, repeat the above sequence until all required channels have been selected.
The last channel selected or de selected using the t key will be the value shown on
the LED when the "ENT" key is pressed and will be the value used for the first
change even if other channels were different. If no channels were selected when the
"ENT" key is pressed, the unit will revert to its normal running display mode.
Press the "ENT" key when all channels required are selected.
After the "ENT" key is pressed, the number 1 LED (right hand LED bar) display
will show number 1 to indicate that it is set point one that will be altered. After
channel selection the sand t keys are used to alter that value for the channel/
channels that was/were selected
If the "ENT" key is pressed without changing the value with the sor t KEYS
all values will remain the same even if some of the channels set points were different
than the last channel that was selected or de selected.

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
KEYBOARD FUNCTIONS CONT..
FUNCTION NUMBERS
1 = Temperature set point (4 set points with time relevance).
2 = Differential set point (the amount of temp change for on/off).
3 = Set point usage Times (4 times with set point number relevance).
4 = High Alarm (4 set points with time relevance).
5 = Low Alarm (4 set points with time relevance).
6 = High Alarm Delay (delay in minutes before the alarm is on).
7 = Low Alarm Delay (delay in minutes before the alarm is on).
8 = Defrosts (sets from 1 to 8 defrosts per 24 hours).
9 = Defrost Auto On Off (allows auto defrosts or no auto defrosts).
10 = Defrost Manual On Off (allows a manual defrost, resets to off
when finished the defrost).
11 = Control On Off (allows auto control or off, all turned off).
12 = Fans Continuous or Automatic (on all the time or only while refrig).
13 = High Alarm Override (stops high alarm from activating if set to off)
14 = Low Alarm Override (stops low alarm from activating if set to off).
15 = Differential Type (whether set point is in the Middle, Top or Bot).
16 = Power On Delay (staggers start up of rooms after a power failure).
17 = Unit Number (for identifying each unit when printing).
18 = Cooling Heating (used to set the unit for Cooling or Heating mode).
19 = Time (sets the real time clock hrs,min,sec,day,date,month & year).
20 = Calibrate Real Time Clock (adjusts real time clock accuracy).
21 = Print (for setting & printing functions).
22 = Data Log (sets the time (& channels) to data log into memory).
23 = Password On Off (makes the password required active or inactive).
24 = Password Change (allows a new password to be set).
25 = Pump Down (allows the pump down of evaporator after turn off).
26 = Display Intensity (varies the brightness of the display).
27 = Daily Set Points (which set points may used for each day of week).
28 = Line Feed Yes/No (whether a unit does a line feed when printing).
29 = Channel Connected (sets which channels are present on the unit).
30 = Channel To Scan (which channels are scanned in the scan mode).
31 = Scan Time (the time between each channels display in scan mode).
32 = Scan Yes No (whether the unit is to scan or not).
33 = Control Channel (which chan is used for control and/or averages)
34 = Reset Maximum & Minimum (resets all to current time & temp).
35 = Baud rate set (sets the baud rate, stop bits = 1 and no parity).
36 = Long Term or Pull Down mode set (sets the suction sol control).

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
SETTING FUNCTIONS
1. TEMPERATURE SET POINTS
Sets the 4 temperature control set points associated with the 4 time set points be-
tween -50 oC. and +150 oC. If in cooling mode only one set of 4 set points. If in
heating mode there is 3 sets of 4 set points required. Control 1, 2 and 3 are available
for 3 banks of heating elements. Control 4 acts as a fans or agitator in the heating
mode and is turned on if any one or combination of the other three control relays are
on. The led's 5, 6 & 7 are lit in the heating mode to indicate which control number is
being set 5 = control 1, 6 = control 2 and 7 = control 3.
FOR COOLING
PRESS “SET”
ENTER PASSWORD IF REQUIRED
PRESS s t TO SELECT NUMBER 1
PRESS “ENT”
1s t TO SELECT REQUIRED SET POINT 1 TEMPERATURE ON LED
PRESS “ENT”
2-4 REPEAT THIS PROCESS FOR SET POINTS 2, 3 & 4
SELECTION COMPLETE
FOR HEATING
PRESS “SET”
ENTER PASSWORD IF REQUIRED
PRESS s t TO SELECT NUMBER 1
PRESS “ENT”
1&5 s t TO SELECT TEMP SET POINT 1 FOR CONTROL 1 ON LED
PRESS “ENT”
2&5 s t TO SELECT TEMP SET POINT 2 FOR CONTROL 1 ON LED
PRESS “ENT”
3&5 s t TO SELECT TEMP SET POINT 3 FOR CONTROL 1 ON LED
PRESS “ENT”
4&5 s t TO SELECT TEMP SET POINT 4 FOR CONTROL 1 ON LED
PRESS “ENT”
2-4 REPEAT THIS PROCESS FOR SET POINTS 1, 2, 3 & 4 FOR CONTROL 2,
& 6-7 & 3
SELECTION COMPLETE
NOTE :- These numbers represent the No. LED lit on the
right hand Bar LED as the "ENT" key is pressed.

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
SETTING FUNCTIONS CONT..
2. DIFFERENTIAL SET POINT
Sets the Differential between +0.2 oC. and +10.0 oC. in 0.2 oC. steps.
PRESS “SET”
ENTER PASSWORD IF REQUIRED
PRESS s t TO SELECT NUMBER 2
PRESS “ENT”
1s t TO SELECT REQUIRED DIFFERENTIAL ON LED
PRESS “ENT”
SELECTION COMPLETE
3. SET POINT USAGE TIMES.
Sets the 4 time set points associated with the control temperature set points and the
High and Low alarm temperature set points. The times can be any time of the day (in
24 hour mode) to the minute, with the following conditions. Time 1 must be the first
time after 00:00 (12 midnight) followed by time 2 etc.. Once time 1 is set the unit
will not allow time 2 to be set to an earlier time and so on for all time set points. If
two or more time set points are set to the same time, the later (if 2 and 3, time 3) will
be the time (and therefore the set point number) used from that time until the next
time set point is reached. See also DAILY SET POINTS for information on the
usage of one or more set points that can be used on any particular day of the week.
PRESS “SET”
ENTER PASSWORD IF REQUIRED
PRESS s t TO SELECT NUMBER 3
PRESS “ENT”
SELECT CHANNELS IF REQUIRED (OPTIONAL EXTRA)
1s t TO SELECT REQUIRED SET POINT 1 TIME ON LED
PRESS “ENT”
2-4 REPEAT THIS PROCESS FOR SET POINTS 2, 3 & 4
SELECTION COMPLETE

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
SETTING FUNCTIONS CONT..
4. HIGH ALARM TEMPERATURE SET POINTS
Sets the 4 High alarm temperature set points associated with the 4 time set points
between -50 oC. and +150 oC.
PRESS “SET”
ENTER PASSWORD IF REQUIRED
PRESS s t TO SELECT NUMBER 4
PRESS “ENT”
SELECT CHANNELS IF REQUIRED (OPTIONAL EXTRA)
1s t TO SELECT REQUIRED HIGH ALARM SET POINT 1 ON LED
PRESS “ENT”
2-4 REPEAT THIS PROCESS FOR SET POINTS 2, 3 & 4
SELECTION COMPLETE
5. LOW ALARM TEMPERATURE SET POINTS
Sets the 4 Low alarm temperature set points associated with the 4 time set points
between -50 oC. and +150 oC.
PRESS “SET”
ENTER PASSWORD IF REQUIRED
PRESS s t TO SELECT NUMBER 5
PRESS “ENT”
SELECT CHANNELS IF REQUIRED (OPTIONAL EXTRA)
1s t TO SELECT REQUIRED LOW ALARM SET POINT 1 ON LED
PRESS “ENT”
2-4 REPEAT THIS PROCESS FOR SET POINTS 2, 3 & 4
SELECTION COMPLETE

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TWITE INSTRUMENTS THERMOSTAT MODEL TD-196 OPERATING MANUAL
SETTING FUNCTIONS CONT.
6. HIGH ALARM DELAY SET POINT.
Sets the High alarm Delay. Disables the high alarm for the time set in minutes (not
including the time the unit is doing a defrost) between 0 and 120 minutes.
PRESS “SET”
ENTER PASSWORD IF REQUIRED
PRESS s t TO SELECT NUMBER 6
PRESS “ENT”
SELECT CHANNELS IF REQUIRED (OPTIONAL EXTRA)
1s t TO SELECT REQUIRED HIGH ALARM SET POINT 1 ON LED
PRESS “ENT”
SELECTION COMPLETE
7. LOW ALARM DELAY SET POINT.
Sets the Low alarm Delay. Disables the high alarm for the time set in minutes (not
including the time the unit is doing a defrost) between 0 and 120 minutes.
PRESS “SET”
ENTER PASSWORD IF REQUIRED
PRESS s t TO SELECT NUMBER 7
PRESS “ENT”
SELECT CHANNELS IF REQUIRED (OPTIONAL EXTRA)
1s t TO SELECT REQUIRED LOW ALARM SET POINT 1 ON LED
PRESS “ENT”
SELECTION COMPLETE