Sub-Zero SZ-7081 User manual

GENERAL DESCRIPTION
The SZ-7081 is single setpoint temperature controller.
It has unique features and user friendly parameters.It is
designed for Heating as well as Cooling applications. In
Heating mode it can work in either Proportional or On-Off
mode.
Additionally the SZ-7081 offers several protection
features that are easily understood by the examples
given in the instruction manual.
The controller can be used for several applications
with mesuring range as below:
J type thermocouple : 0 C 0 C
type thermocouple : 0 C C
C C
C C
O O
to 70
O O
K to 999
O O
2 Wire RTD : -99 to 850
O O
3 Wire RTD : -99.9 to 99.9
OPERATING
INSTRUCTIONS
SZ-7081
INDIA
www.ascontrols.com
INDEX
To set cycle Time in seconds. Activated in Proportional
mode only.
To set relay mode as per application.
Parameter
Parameter setting
method.
To set Cutout value of the Controller.
To select the type of sensor.
To select type of output.
To set Control Action of Output.
To set Hysterisis (differential). Activated in On-Off mode
only.
To set Proportional Band. This parameter is activated in
Proportional Mode only.
To set Time Delay. This parameter is activated in On-Off
Mode only.
To set manual offset for proportional band. Activated in
Proportional mode only.
To set maximum limit for set point as per the sensor
selected.
To set minimum limit for set point as per the sensor
selected.
To set Probe calibration.
To restore default settings.
To end programming.
To lock keypad.
To display set point. The Set point can not be changed but
can only be viewed in this mode.
Operating Messages
Technical Data
Wiring Diagram
Panel cutout & Installation
Pg. No.
1
1
2
3
3
4
4
5
6
6
7
8
8
9
10
10
10
11
12
14-16
13

Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Function: To display set point.
The Set point cannot be
changed but can only be
viewed in this mode.
Viewing Set
Points
Display will show the value of
set point
If you Press SET key, the
control goes into the normal
mode.
Display will show “ ” &
flash.
Function: To set Cutout value
of relay/SSR.
Use UP/DOWN keys to get
desired value . After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
Once the set key is pressed,
the control goes into the
normal mode.
SET mode
Press and
hold
SET key for
0.5 second
and release
Press and
hold
SET key for
2 seconds
and
release.
Set
point(SET)
To change
the “ ”
parameter,
press SET
key.
Program modeTo set other
parameters.
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Display will show “ ” &
flash.
To go to other parameters,
use up / down keys.
Hold
down/prg
key for 2
seconds.
Function: To select the type
of sensor.
Sensor
Type
Use UP/DOWN keys to get
desired value. .After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
: J type Thermocouple
: K type Thermocouple
: 2 wire RTD
: 3 wire RTD
Note : If sensor type is
changed ,following
Parameter will be changed to
their factory set values.
HSLt = 700(J) / 999(K) /
850(rtd2) / 99.9(rtd3) ,
LSLT = 0(J/K),-99(rtd2),
-99.9(rtd3)
CALb =0 & Set point =0
To change
the “ ”
parameter,
press the
SET key.
1
2Function: To select the type
of output.
Output Type
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
- Relay
- SSR
To change
the “ ”
parameter,
press the
SET key.
Function: To set relay mode
as per application.
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
- Heating (Forward)
- Cooling (Reverse)
Relay Mode
To change
the “ ”
parameter,
press the
SET key.
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Function: To set Proportional
Band .This parameter is
activated in Proportional
Mode only.
Proportional
Band
O
0.1 C O 99.9 C O 10.0 C
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
This is the proportional band
set in degrees.
To change
the “ ”
Parameter,
press the
SET key.
5
3
Function: To set Control
Action of Output.
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
- On- Off mode
- Proportional
Note : If “H-C” parameter is
selected as “Cool”, Control action
can not be selected as ”ProP”
Control
Action
To change
the “ ”
parameter,
press the
SET key.
4
o
Example: If Set point is 60 C &
o
Proportional band(Prbd) is 10 C
then, proportional action takes
o o
place between 50 C to 60 C.
1 2
34
Note: If “H-C” is selected as
“CooL” (cooling mode), “CtrL”
parameter (Control action) will
be set to “onoF”.
set
prg
set

Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Example (In cooling mode) :
O
If the set point is 40.0 C and
O
Hysterisis is set at 2.0 C then,
when the system reaches
O
40.0 C, the comp. Relay will
cut out. Since the Hysterisis is
O
2.0 C, the comp. Relay will cut
O
i n ( re s t a r t ) a t 4 2 . 0 C
O O
(40.0 C+2.0 C ).
(In Heating mode) : If the set
O
point is 40.0 C and Hysterisis
O
is set at 2.0 C then, when the
O
system reaches 40.0 C, the
Relay will cut out. Since the
O
Hysterisis is 2.0 C, the Relay
wi l l c u t i n ( r e s t a r t ) a t
O O O
38.0 C(40.0 C-2.0 C ).
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Example : If Cycle Time is
set to 10 sec, the duty cycle
of Relay/SSr ON-OFF in
proportional band will be
10 sec.
ON time +OFF time = 10 sec
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Function: To set Time Delay.
This parameter is activated in
On-Off Mode only.
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
This parameter is used to
protect the compressor from
restarting in a short period of
time.
Time Delay
To change
the “ ”
Parameter,
press the
SET key.
0 Min 20 Min 0 Min
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key &
display will show “- - - -” which
confirms that value has been
stored in memory.
To change
the “ ”
Parameter
press the
SET Key
Function: To set minimum
limit for set point as per the
sensor selected.
Lower set
Limit
8
Function: To set maximum
limit for set point as per the
sensor selected
Higher set
Limit
Set
point
O
700 C
(J)
O
999 C
(K)
O
850 C
(Rtd2)
O
99.9 C
(rtd3)
O
700 C
9
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
To change
the “ ”
Parameter
press the
SET key.
O
0 C (J)
O
0 C(K)
O
-99 C
(rtd2)
O
-99.9
C
(rtd3)
Set
point
O
0 C
10
Function: To set cycle Time in
seconds. Activated in
Proportional mode only.
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
Cycle Time
To change
the “ ”
parameter
press the
SET key.
1 sec 99 sec 20 sec
6
Function: To set manual
offset for proportional band.
Activated in Proportional
mode only.
Manual
Offset
O
-99.9 C O 99.9 C O 0.0 C
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory. This
parameter decides the
position of Proportional band.
To change
the “ ”
parameter
press the
SET key.
7
Example : If this parameter is set
to 3 minutes, the Relay will cut off
at the set temperature, but will not
restart for 3 minutes even if the
differential is achieved earlier.
This parameter is good to protect
the life of the compressor or even
in applications where the probe is
placed at places where there are
sudden & short changes in
temperature.
Example : Setting this parameter
O
at 60.0 C will not allow the set
O
point to go above 60.0 C. Also, if
O
the temperature reaches 60.0 C
or above, the display will show Ht
(High Temp) indicating that the
temperature has gone above the
range in this parameter.
5 6
78
Function: To set Hysterisis
(differential) Activated in On-
Off mode only.
Hysterisis O
0.1 C O 99.9 C O 2.0 C
5.1
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
This parameter value is the
differential between cut out
and cut-in temperature.
To change
the“ ”
parameter,
press the
SET key.
O
Example : If “ ” is 0.0 C
O
,Set point is 60 C, Prbd =
O
10.0 C ,then proportional
O O
ba n d i s 5 0 C t o 60 C
(Proportional action will take
O O
place between 50 C to 60 C).
But for the same settings of
Set point and Prbd, if “ ” is
O
set to 5.0 C, then proportional
O O
band will be 55 C to 65 C.
Contd.
Contd.

RST
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Function: To restore default
settings.
Function: To lock keypad.
Function: To end
programming.
Reset
Parameter
Keypad
Lock
END
Parameter
When set to “ ”, all
parameters are programmed to
factory set values.
Useful to debug setting related
problems.
Once the set key is pressed,
the control goes into the
normal mode.
To change
the “ ”
parameter
press the
SET key.
To end
programm-
ing, press
the SET key
13
12
14
Example : Setting this
O
parameter at 20.0 C will not
allow the set point to go
O
below 20.0 C. Also, if the
O
temperature reaches 20.0 C
or goes below, the display will
show Lt (Low Temp)
indicating that the
temperature has gone below
the value in this parameter.
Operating messages
Description
Temperature equal or above the maximum limit of the set point.
(“ ”)
Temperature equal or below the minimum limit of the set point.
(“ ”)
Probe circuit open or without probe, or for temperature out of
given range.
9 10
11 12
Use UP/DOWN keys to set
desired range. After setting the
desired range, press the set key
and you will see "- - - -” which
confirms that the value has been
stored in memory.
This parameter locks the keypad
so that tampering is not possible
by bystanders.
= keypad unlocked
= keypad locked
When locked , all the parameters
can only be viewed, but can't be
modified. When you enter the
parameter it will display “ ”
and then it will show the value of
parameter.
To change
the “ ”
parameter
press the
SET key.
Technical Data
Housing : ABS Plastic
Dimensions : Front : 75.5x35 mm
Depth : 87 mm
Mounting : Flush panel mounting with fasteners.
Protection : Front panel is waterproof & I.P. 65 rated.
Connection : Screw terminal blocks. .5mm2
one wire/terminal only.
Data Storage : Non-Volatile EEPROM Memory
O O
Storage temp : -20 C to 70 C(non-condensing)
O
Accuracy : +/-1 C
Power Input : 230Vac +/-10%, 50-60Hz
O O
Operating Temp : 5 C to 50 C(non-condensing)
Sensor Type : RTD/ J / K
Resolution : 0.1°C 3 wire RTD & 1°C for 2 wire RTD ,J, K .
Display : 4 digits display,size 0.56” (7 segments)
LED status : 1.Relay On/Off
2.SSR On/Off
3. “J”
4. “K”
5.“RTD”
Control Action : 1. Proportional
: 2. On-Off
Relay Mode : Heating / Cooling.
Input : Tc J or Tc K or RTD 2/3 wires
Output : Relay / SSR ( selectable )
Probe Fail
Control Action : Relay OFF
Contacts : C-NO-NC
1
Message
Press RST key to come out of Program/Set mode immediately.
If Controller is in Program or Set mode and RST key is
pressed it will come to the normal mode.
Function: To set Probe
calibration.
Use UP/DOWN keys to get
desired value. After setting
desired value press SET key
& display will show “- - - -”
which confirms that value has
been stored in memory.
Probe
Calibration
To change
the “ ”
parameter
press the
SET key.
O
-20 C/
-20.0
OC
(rtd3)
O
20 C/
O
20.0 C
(rtd3)
O
0 C
11
Example : The temperature on
O
the display is 28.0 C, whereas
the actual temperature is
O
30.0 C. You will need to set the
“ ” parameter to 2.0, which
means that once out of the
programming mode, the
O
temperature will show 30.0 C
O O
(28.0 C + 2.0 C)

13 14
16
Notice: The information in this document is subject to change in
order to improve reliability , design or function without prior notice
and does not represent a commitment on the part of the company.
In no event will the company be liable for direct, indirect, special,
incidental or consequential damage arising out of the use or
inability to use the product or documentation, even if advised of the
possibility of such damages. No part of this manual may be
reproduced or transmitted in any form or by any means without the
prior written permission of the company.
Disclaimer: This manual & its contents remain the sole property of
A.S. CONTROLS Pvt. Ltd, India and shall not be reproduced or
distributed without authorisation. Although great care has been
taken in the prepartion of this document, the company or its
vendors in no event will be liable for direct, indirect, special,
incidental or consequential damage arising out of the use or
inability to use the product or documentation, even if advised of the
possibility of such damages. No part of this manual may be
reproduced or transmitted in any form or by any means without the
prior written permission of the company. A.S. CONTROLS Pvt.
Ltd, reserves the right to make and changes or improvements
without prior notice.
Warranty: This product is warranted against defects in materials
and workmanship for a period of one year from the date of
purchase. During the warranty period, product determined by us to
be defective in form or function will be repaired or, at our option,
replaced at no charge. This warranty does not apply if the product
has been damaged by accident, abuse, and misuse or as a result of
service or
modification other than by the company. This warranty is in lieu of
any other warranty expressed or implied. In no event shall the
company be held liable for incidental or consequential damages,
such as lost revenue or lost business opportunity arising from the
purchase of this product.
SZ-7081
set
prg
RST
2
8888
RLY SSR J RTDK
29
70.5
87 mm
Max
15 mm
34.5
WIRING DIAGRAM
SZ-7081
NC
NO C
SSR
TC+
TC-
RTD
RELAY
SHORT FOR 2 WIRE RTD
+
711
10
98
5
3 4
16
12 V
230V
Neutral
Phase
O
C
WIRING: The probe and its corresponding wires
should never be installed in a conduit next to control or
power supply lines. The electrical wiring should be
done as shown in the diagram. The power supply
circuit should be connected to a protection switch. The
terminals admit wires of upto 1.5 sq mm.
WARNING: Improper wiring may cause irreparable
damage and personal injury. Kindly ensure that wiring
is done by qualified personnel only.
Maintenance: Cleaning: Clean the surface of the
controller with a soft moist cloth. Do not use abrasive
detergents, petrol, alcohol or solvents.
CAUTION
Controller :Controller should be installed in a place
protected by vibration, water and corrosive gasses and
where ambient temperature does not exceed the values
specified in the technical data.
Probe :To give a correct reading, the probe must be
installed in a place protected from thermal influences,
which may affect the temperature to be controlled.
15
Installation : Fixing and dimensions of panel models:
To fix the unit, slide the fastener 1 through the guides 2 as
per the position shown in the figure. Move the fastener in
the direction of the arrow, pressing tab 3 it permits to move
the fastener in the opposite direction of the arrow. Once the
controller has been connected, they should be covered with
the lid 4 .Silicon sealant should be applied along the
perimeter of the panel cut out or a rubber ‘O’ ring supplied
before the unit is fitted to obtain IP65 grade.

INDIA
Ball Valves
Globe Valves
Hand Valves
Flow Switches
Solenoid Valves
OUR OTHER PRODUCTS
Cold Room Controller
Chiller Controller
Two Compressors Controller
Heating Controller
Humidity Controller
Pressure Controller
TM
00 / 15.03.10