PVR sub-zero SZ-7534 User manual

SZ-7534
OPERATING
INSTRUCTIONS
www.pvrcontrols.com
INDIA
Minimum allowable low temperature limit.
Compressor differential.
Room probe offset calibration (cold room probe).
Drip time for defrost water to drain out.
Time delay between Compressor relay restart
time.
Compressor relay status on probe (room probe)
failure.
INDEX
To set others parameters.
Cutout point of the Controller.
Maximum allowable high temperature limit.
Time delay between Evap. Fan relay restart time.
Evap. Fan stop temp. (Coil).
Evap. Fan operation when Compressor is off.
Evap. Fan Differential.
Coil probe offset calibration (evap. fan coil probe).
Evap. Fan status during defrost.
3
3-4
4
4-5
5
5-6
6
7
7
8
7-8
8
9
9
10
10
Quick freeze set point.
10
Activate power up defrost cycle.
Quick Freeze time duration.
10-11
E2 Type of computation for defrost frequency.
E3 Defrost frequency.
E4 Maximum Defrost duration.
E5 Defrost stop temperature (Evap. Coil probe).
12
12
13
13
E6 Alarm on heater function fault. 14
E8
E7
Maximum Defrost duration on Coil probe fail.
Display during defrost.
AL Power on time delay for Alarm.
FS Revert to factory set parameter.
LP Lock Keypad.
EP End programming.
Operating Messages for Faults.
Operating Messages and Icon status.
PARAMETER
14
14
16
15
15
16
16
17
Technical Data.
Connection Diagram.
18
19
Introduction
Get to Know your Controller
Items Included
Key Introduction
Parameter List
1
1
1
2
3
DESCRIPTION Pg.
No.
INDEX
PARAMETER DESCRIPTION Pg.
No.
P3
P4
P5
P7
P6
P8
Set Point
P2
L2
L1
Sensing logic for HP/LP/OSS.
do
L3
L4
L5
L6
CS
E0
Ct
E1 Type of defrost. 11
Cyclic OFF time. 7
OFF time
Cyclic ON time.
On time
7
Panel cutout & Dimensions. 20

Ÿ2 NTC probe for cold room temp. + evap. Coil
temperature.
ŸAudible alarm.
ŸAuto/Man defrosting facility(Time/Temp based).
ŸSpecial software to indicate probable heater fault.
Ÿ 7 Segment to display all parameters.
ŸRange: -50.0°C to +50.0°C (0.1°C res.).
ŸRelay outputs: Compressor + Light + Heater +
Evap. Fan .
ŸDigital Inputs: 1 nos, (a) Pressure cutout.
ŸHP/LP/OSS trip protection for compressor.
ŸCompressor protection algorithm.
set
prg
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
Set Point
P2
Parameter
To change
the P2
parameter,
press the
set key
To set
others
parameters.
Press and
hold set key
for 2
seconds
and release
2 seconds.
Press &
Hold
DOWN(prg)
key for
Function : To set the cutout
point of the Controller.
Function : To set maximum
allowable high temperature
limit.
Use UP/DOWN keys to set
desired value.
Ones set at a particular
value, this will not allow the
set point to go above this
value and below Quick
Freeze Set point.
SP = Set Point.
Example : Setting this
parameter at -25.0°C will not
CS = Quick Freeze set point.
P2 = Max allowable high temp.
limit.
Display will change to set value
and set value will flash on
display. The set point value can
now be changed by using
UP/DOWN key. After setting the
desired value, press the set key
and you will see “- - -” which
confirms that the set point has
been stored in memory.
Display will show P2 & will
flash. To go to other
parameters, use up/ down
keys.
(CS+
0.1)°C
(SP+
0.1)°C
(P2-
0.1)°C
50.0
°C
0.0°C
50.0
0C
1
2
1 2
34
SZ-7534
RST
2
prg SET
2
Get to Know your Controller
LED INDICATIONS
7 Segment
Display Down &
Program Key
UP & Quick
Freeze Key
SET Key Reset &
ON/OFF Key
Defrost Key
Light Key
Introduction
Items Included
NO.
1.
2.
QTY
ITEMS
CATALOG
2
1
NTC SENSOR 1.5 METER
Key Introduction
Quick
Freeze
This key used to put controller in quick freeze
mode. To activate this mode press QF key for 4
seconds. The compressor operates in this mode
for time duration set through quick freeze time
duration (Ct) parameter and set pint through Quick
freeze set point (CS) parameter, UP key.
Manual
defrost
To force a manual defrost, press defrost key for 4
seconds. The unit will go into defrost mode. If E4
parameter is set to 0, or coil temp. is greater than
defrost stop temp. (E5) this key remain inactive.
Power
Switch
Light Switch
This key will mute the buzzer and reset the alarm
relay.(single press).
This key will press for 5sec to switch off controller.
This key used to switch on Light.
RST
prg
SET
Program
Key
This key used to do programming in controller,
Down key.
This key used to set the value.
Set Key
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
To change
P3
parameter,
press the
set key
Use UP/DOWN key to set
desired value.
Use UP/DOWN keys to set
desired value.
Ones set at a particular
value, this will not allow the
CS (QF Set Point) to go
below this value.
Example : Setting this
parameter at -30.0°C will not
allow the CS point to go
below -30.0°C. Also, if the
temperature reaches -30.0°C
, the display will show Lt (Low
temp) indicating that
temperature has gone below
the value in this parameter
and at this point the alarm
and buzzer will come on.
P4
Parameter
Function : To set the comp.
differential (hysteresis).
0.5°C 20.0
°C
2.0 °C
4
P3
Parameter
Function : To set minimum
allowable low temperature
limit.
-50.0
0C
(CS -
0.1)°C
-50.0
0C
3
allow the set point to go
above -25.0°C. Also, if the
temperature reaches -25.0 °C
, the display will show Ht
(High temp) indicating that
temperature has gone above
the value in this parameter
and at this point the alarm
and buzzer will come on.
I5.2 prg SET
2
To view coil probe temp. press Down & Set key.

8
7
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
To change
P7
parameter,
press the
set key
Use UP/DOWN key to set
desired value.
Example : If this parameter set
at 3 minutes, the relay will cutoff
at set temperature, but will not
restart for a minimum of 3
minutes, even if the differential
is a chieved 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 and short changes
in temperature like above a cold
room door.
This parameter is used to
protect the compressor from
restarting in a short period of
time.
Use UP/DOWN key to set
desired value.
Example : if this parameter is
set to 2 minutes, then for 2
minutes the Fan, Compressor,
Heater will stay off so that the
defrost water can drip and drain
out.
This is time for which the Fan,
Co m pre s so r, C on d e ns e r,
Heater will stay OFF so that the
defrost water can drip and drain
out.
P7
Parameter
Function: To set drip time for
defrost water to drain out.
0 Min 20 Min 1 Min
7
P8
Parameter
Function: To set comp. Relay
status on room probe failure.
0 2 1
8
To change
P8
parameter,
press the
set key
Use UP/DOWN keys to set
desired value.
0 = Compressor relay ON.
1 = Compressor relay
'on' minutes and 'oF'
minutes(see next two
parameter). (see Sr. 9A
and 9B)
performs a duty cycle of
2 = Compressor relay OFF.
To change
P6
parameter,
press the
set key
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
On time
Parameter
If P8=1, Cyclic ON time. 2 Min 60 Min 10 min
8A
Use UP/DOWN key to set
desired value. This is cyclic
ON time. This parameter will
be active only when P8 = 1.
To change
on
parameter,
press the
set key
Off time
Parameter
If P8=1, Cyclic OFF time. 3 Min 20 Min 4 Min
8B
Use UP/DOWN key to set
desired value. This is cyclic
OFF time. This parameter will
be active only when P8 = 1.
To change
oF
parameter,
press the
set key.
do
Parameter
Function : To set sensing
logic for HP/LP/OSS.
0 1 1
9
Use UP/DOWN keys to set
desired value.
To change
do
parameter,
press the
set key
L1
Parameter
Function : Evap. Fan stop coil
temp. 0C
-50.0 50.0
0C
0
2.0 C
10
56
Fact.
Set
Range
Max
10.0°
C
0.0°C
30 Min 3 Min
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Min
To change
P5
parameter,
press the
set key
In time it may be possible that
the temp. on display may be
offset by a degree or so. To
compensate for this error, you
may need to add or minus the
degrees required to achieve
the correct temperature.
Use UP/DOWN key to set
desired value.
Example : The temperature
on the display is 28.0°C,
w h e r e a s t h e a c t u a l
temperature is 30.0°C. You will
need to set this parameter to
2.0°C, which means that once
out of programming mode, the
t e m p e r a t u r e w i l l s h o w
30.0°C(28.0°C + 2.0°C).
P5
Parameter
Function : To set room probe
offset calibration.
-10.0
°C
5
P6
Parameter
Function: To set time delay
between comp. relay restart
time.
0 Min
6
Example : If the set point is set
at 10.0 °C and differential is set
at 2.0°C, then when the
system reaches 10.0 °C, the
comp. Relay will cutout. Since
the differential is 2°C, the
comp. Relay will cutin at
12.0 °C (10.0°C + 2.0°C).
Differential between cutout
and cutin temperature can be
set between 0.5 °C to 20.0 °C.
To change
P4
parameter,
press the
set key
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
To change
L3
parameter,
press the
set key
Use UP/DOWN keys to set
desired value.
1 = Evap. fan will be stay ON
when compressor will be
compressor is OFF.
0 = Evap. fan OFF when
off.
L3
Parameter Function : Evap. Fan
operation when compressor
is off.
0 1 1
12
Use UP/DOWN keys to set
desired value.
This setting is used to limit
maximum temperature
beyond which the evap. fan
will cutoff.
To change
L1
parameter,
press the
set key
L2
Parameter
Function : To set time delay
between evap. fan relay
restart time.
0 Min 99 Min 1 Min
11
To change
L2
parameter,
press the
set key
Use UP/DOWN keys to set
desired value.
Example : If this is set 3
minutes, the evap. fan relay
will cutoff at the temp. set by
L1 parameter but the fan will
not come on for a minimum of
3 minutes if L4 is achieved
earlier.
0VDC present.
0 = P/LP/OSS fault with
12VDC present.
1 = HP/LP/OSS fault with

11 12
E1
Parameter
Function : To set type of
defrost.
0 3 0
19
To change
E1
parameter,
press the
set key
2 = Time based defrost,
independent of evap coil
probe temperature. Works
with E4 time duration.
Comp. Condenser, Heater
will be off during this type
of defrost.
1 = Hot gas defrost where
compressor on, heater on.
3 = No defrosting.
Use UP/DOWN keys to set
desired value.
0 = Heater defrost in which
case compressor off,
heater on.
Fact.
Set
Range
Min Max
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
E2
Parameter
Function : To set type of
computation for defrost
frequency.
0 1 0
20
To change
E2
parameter,
press the
set key
0 = Total of real time.
This means that the time
ca l c u l a t i o n f o r d e f ro s t
frequency will be for the total
hours the unit has been
running.
Example : If E3 is set to 6 hrs and
3:40 hrs have passed after unit
has started and power fails, then
defrost cycle will start after 3:30
hours when power resumes.
1= Sum of total compressor
operating times. This means
that for time calculation, the
unit will add the total time the
compressor has been in an
ON mode.
it keeps a records of the number
of hours worked +/- ½ hour,
incase of a power failure.
Use UP/DOWN keys to set
desired value.
Ct
Parameter
To change
Ct
parameter,
press the
set key
Function : To set Quick
Freeze time duration.
Use UP/DOWN keys to set
desired value.This is the
maximum amount of time
allowed for Quick freeze. If set
to 0, there will be no quick
freeze.
Example : See CS parameter
0 HRS 30 HRS 0 HRS
17
CS
Parameter
Function : To set quick freeze
set point.
16 (P3+0.
O
1) C
(SP-
O
0.1) C
O
-5.0 C
To change
CS
parameter,
press the
set key
Use UP/DOWN keys to set
desired value.
Example : If this is set to -5°C,
and quick freeze time duration
is set to 1 hr, then when it is
set to quick freeze mode, the
compressor will take -5°C set
point for 1 hr.
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
To change
E0
parameter,
press the
set key
Example : This parameter will
help to achieve first defrost
cycle in short amount of time
after power on. If E3 < E0 then
power up defrost cycle will be
ignore as frequency defrost
cycle achieved before power
up defrost cycle.
2 = Power up defrost after 2 Hr.
0 = No power up defrost.
Use UP/DOWN keys to set
desired value.This parameter
will decide to start power up
defrost or not.
1 = Power up defrost after 1 Hr.
3 = Power up defrost after 3 Hr.
To change
L6
parameter,
press the
set key
0 = Evap. fan will stay on during
1 = Evap. Fan will stay off during
defrost.
Use UP/DOWN key to set
desired value.
defrost.
9 10
L4
Parameter
Function : Evap. fan
differential (hysteresis).
0
0.5 C 0 20.0 C 0 2.0 C
13
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
L6
Parameter
Function : Evap. fan status
during defrost.
0 1 1
15
L5
Parameter
Function : To set coil probe
offset calibration (evap. fan
coil probe).
0C
-10.0 10.0
0C
0
0.0 C
14
To change
L5
Parameter,
press the
set key
In time it may be possible that
the temp. on LCD display may
be offset by a degree or so. To
compensate for this error, you
may need to add or minus the
degrees required to achieve
the correct temperature.
Example : The temperature
on the LCD is 28.0°C,
whereas the actual
temperature is 30.0°C. You will
need to set this parameter to
2.0°C, which means that once
out of programming mode, the
temperature will show
30.0°C(28.0°C + 2.0°C).
Use UP/DOWN keys to set
desired value.
To change
L4
Parameter,
press the
set key
Use UP/DOWN keys to set
desired value.
Example : If L1 parameter is
set to 2.0°C, and the L4 is set
to 2.0°C, then evap. fan will cut
off at 2.0°C and restart only at
0.0°C.
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
1 HRS 31 HRS 6 HRS
To change
E3
parameter,
press the
set key
E3
Parameter
Function : To set defrost
frequency.
21
Use UP/DOWN keys to set
desired value.
This is the amount of time
between two defrost cycles.
Example: If this parameter is
set to 1, then when comp. OFF,
evap. fan will remain ON.
E0
Parameter
Function : To set activate
power up defrost cycle.
0 3 0
18

AL
Parameter
Function : To set Power on
time delay for Alarm(HT/LT).
0min 30min 30min
27
To change
AL
parameter,
press the
set key Example : If you set this
parameter to 20min, once the
power is switch on, the alarm
for Ht/Lt will not activate for 20
minutes after the power is
switched on. This is most
useful to avoid the nuisance
alarms when the ambient are
h i g h w h e n m a c h i n e i s
switched on after long time.
Use UP/DOWN key to set
desired value.
15 16
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
E8
Parameter
Function : To set maximum
defrost duration on coil probe
fail.
1min 10min 5min
26
To change
E8
parameter,
press the
set key
Use UP/DOWN keys to set
desired value.
This is the maximum amount
of time allowed for a defrost
during coil probe fail.
Example : If this is set to 5
minutes, then defrost for 5
min will take place during coil
probe fail.
Parameter
LP
To change
LP
parameter,
press the
set key
Function : To lock keypad.
Use UP/DOWN key to set
desired value.
O n a c t i v a t i o n , a l l t h e
parameters can only be
viewed but not modified.
1 = activates keypad lock.
This parameter can lock the
keypad so that tampering is
not possible by by-standers.
0 = d-activates keypad lock.
28 0 1 0
FS
Parameter
Function : Revert to factory
set parameter.
0 1 0
29
To change
FS
parameter,
press the
set key
Useful to debug setting
problems. When set to 1, all
parameters are programmed
to factory set vales.
1 = Revert to factory set
parameters.
Use UP/DOWN keys to set
desired value.
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
14
Description of parameters and functions.
Sr.No.
Parameter
Parameter setting
method.
Fact.
Set
Range
Min Max
E6
Parameter
To change
E6
parameter,
press the
set key
24 Function : To set Alarm on
heater function fault.
0 = No buzzer or indication.
Use UP/DOWN keys to set
desired value.
1 = Buzzer will come on incase
the temperature of the coil
has not risen by 10°C
within 50% of the defrost
time (E4).
Activated when E1 = 0 (Heater
defrost).
0 1 0
E7
Parameter
To change
E7
parameter,
press the
set key
25 Function : To set display
during defrost.
during defrost.
1 = display will show ' dF'
0 = Display will show room
Use UP/DOWN keys to set
desired value.
temperature.
0 1 0
13
Operating Messages for Faults
MESSAGES FAULTSSL. NO
HP HP/LP/OSS Trip1
PP Probe fail (Room) 2
Ht High temperature.3
Lt Low temperature.4
LP Lockpad when LP = 1.5
oFF Controller Switch off using Power Key.6
E5
Parameter
To change
E5
parameter,
press the
set key
23 Function : Defrost stop
temperature (Evap. coil
probe).
This is the maximum
temperature allowable at
which the defrost process will
stop.
Example : If this parameter is
0
set to 7 C, then if defrosting
is in progress then when E5
0
temperature reaches 7 C, the
defrost process will stop.
Use UP/DOWN keys to set
desired value.
-50.0
0C
50.0
0C
0
8.0 C
Example : If this parameter is
set to 15 minutes, and
Defrost frequency parameter
is set at 1 hr. Then 1hr after
power is applied to the
controller, defrosting for 15
minutes will take place. This
cycle will repeat every 1 hr.
E4
Parameter
Function : To set Maximum
Defrost duration.
22
To change
E4
parameter,
press the
set key
If set to 0, there will be no
defrost cycle.
This is the maximum amount
of time allowed for a defrost.
Use UP/DOWN keys to set
desired value.
0 Min 99 Min 30 Min
EP
Parameter
To End
Programming
press the set
key
Function : To End
programming.
Once the SET key is pressed
the control goes into the
normal mode and displays the
temperature.
30

17 18
Technical Data:
Connections : Male Spade Connectors.
0 0
Operating Temp. : 5 C to 50 C(non-condensing).
0 0
Storage Temp. : -20 C to 70 C(non-condensing).
Defrost Relay : 10A/12VDC(res.).
Input : 2 NTC Probe, SZ-N75.
0
Accuracy : +/- 1 C.
Mounting : Flush panel mounting.
Power Input : 230Vac
Housing : Black, ABS Plastic.
Data Storage : Non-Volatile EEPROM Memory.
Front Cover : Polycarbonate plastic.
Panel Cutout : 150mm X 31mm.
Range : -50.0°C to +50.0°C (0.1°C res.).
00
Probe Tolerance at 25 C : +/-0.3 C.
Front Protection : Front panel is water proof & IP64 rated.
Display : 3X14.2mm(0.56”) LED.
Compressor Relay : 20A/12VDC(res.).
Fan Relay : 10A/12VDC(res.).
Light Relay : 10A/12VDC(res.).
0
Resolution : 0.1 C.
19
Suggested Connection Diagram
20
SZ-7534 prg SET
RST
2
2
36 mm
185.5 mm
32.2 mm
134 mm
65.60 mm
56.55 mm 21.6 mm
30 mm
36 mm
15.5 mm
Panel Cutout
150mm
31mm
I5.2
Operating Messages and Icon status
Drip time On.
L2, L1, L4,
P7
Comp. Relay On.
Comp. Relay Off.
Comp. Relay Timedelay.
Buzzer On.
On
Off
Flashing
On
On
Message Description ParameterMode
SP, P4, P6
Fan Relay Timedelay.
Fan Relay On.
Fan Relay Off.
2
On
Off
Flashing
Flashing Coil Probe fail.
AL
1 2 345678 9 10 11 12 13 14 15 16 17
COIL ROOM
NC
NO
NO
NO
NC
NO
+ 12VDC
Digital input
from Pressure
(HP/LP/OSS)

INDIA
Ball Valves
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Flow Switches
Solenoid Valves
00 / 29.09.11
Cold Room Controller
Chiller Controller
Two Compressors Controller
Heating Controller
Humidity Controller
Pressure Controller
TM
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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.
Disclaimer: This manual & its contents remain the sole
property of PVR CONTROLS, India and shall not be
reproduced or distributed without authorization. Although
great care has been taken in the preparation 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. PVR CONTROLS reserves the right to make and
changes or improvements without prior notice.
22
21
CAUTION
Maintenance: Cleaning: Clean the surface of the
controller with a soft moist cloth. Do not use abrasive
detergents, petrol, alcohol or solvents.
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.
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 2.5sq. mm.
WARNING: Improper wiring may cause irreparable
damage and personal injury. Kindly ensure that wiring is
done by qualified personnel only.
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.
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.