Innovative instruments i-therm AI-7481, i-therm AI-7781, i-therm AI-7981, i-therm AI-7881, i-therm AI-7681 User's Operating Manual

i

AI - 7481

(48 X 48)

AI - 7781

(72 X 72)

AI - 7981

(96 X 96)

AI - 7681

(96 X 48)

AI - 7881

(48 X 96)

USER’S OPERATING M AN UA L FOR PID DIGITAL TEMPERATURE CONTROLLER

(Models: AI 7481 / 7781 / 7981 / 7681 / )7881

1. DISPLAY TYPE : Dual 4- Digit 7 segment LED

4 Digit Bright Red (PV)
4 Digit Luminous Green (SV)

STATUS LED’S : OP 1 : Main Control Output

2. INPUT
Sensor input : TC : J,K,R,S,N,T,B

RTD : Pt-100

Range : Refer below table.

Sampling Time : 125 msec.
Resolution : 1°C/0.1°C(Only for RTD)
CJC for TC : Built in automatic
LWC for Pt-100 : Built in upto 18E max.
Digital Filter : 1 to 10 Sec.

3. RELAY OUTPUT
Contact type : N/O, CM, N/C
Contact Rating : 5A @ 250VAC or 30 VDC
Life expectancy : > 5,00,000 operations
Isolation : Inherent

4. SSR DRIVE OUTPUT
Drive Capacity : 12V @ 30mA.
Isolation : Non-Isolated.

5. FUNCTION
Output 1 : Main Control output
Control Action : ON-OFF/PID (Select)
Control Mode : Heat/Cool (Select)

6. ENVIRONMENTAL
Operating Range : 0 ~50°C, 5~90% Rh
Storage Humidity : 95% Rh (Non-condensing)

7. POWER SUPPLY
Supply Voltage : 90~270VAC, 50/60Hz.
Consumption : 4W Maximum.

8. PHYSICAL
Housing : ABS Plastic.

SPECIFICATIONS : -

SAFETY INSTRUCTION :

This controller is meant for temperature control
applications. It is important to read the manual prior to
installing or commissioning of controller. All safety
related instruction appearing in this manual must be
followed to ensure safety of the operating personnel
as well as the instrument.

GENERAL

v The controller must be configured correctly for intended

operation. Incorrect configuration could result in
damage to the equipment or the process under control or
it may lead personnel injury.

v The controller is generally part of control panel and in

such a case the terminals should not remain accessible
to the user after installation.

MECHANICAL

v The Controller in its installed state must not come in

close proximity to any corrosive/combustible gases,
caustic vapors, oils, steam or any other process by­products.

v The Controller in its installed state should not be

exposed to carbon dust, salt air, direct sunlight or radiant

heat.

v Ambient temperature and relative humidity surrounding

the controller must not exceed the maximum specified
limit for proper operation of the controller.

v The controller in its installed state must be protected

against excessive electrostatic or electromagnetic
interferences. Ventilation holes provided on the chassis
of the instrument are meant for thermal dissipation
hence should not be obstructed in the panel.

ELECTRICAL

v The controller must be wired as per wiring diagram & it

must comply with local electrical regulation.

v Care must be taken not to connect AC supplies to low

voltage sensor input.

v Circuit breaker or mains s/w with fuse (275V/1A) must be

installed between power supply and supply terminals to
protect the controller from any possible damage due to
high voltage surges of extended duration.

v Circuit breaker and appropriate fuses must be used

for driving high voltage loads to protect the controller
from any possible damage due to short circuit on loads.

v To minimize pickup of electrical noise, the wiring for low

voltage DC and sensor input must be routed away from
high current power cables. Where it is impractical to do
this, use shielded ground at both ends.

v The controller should not be wired to a 3-Phase supply

with unearthed star connection. Under fault condition
such supply could rise above 264 VAC which will damage
the controller.

v The Electrical noise generated by switching inductive

loads might create momentary Fluctuation in display,
alarm latch up, data loss or permanent damage to the
instrument.
To reduce this use snubber circuit across the load.

v It is essential to install a over Temp. Protection device to

avoid any failure of heating system. Apart from spoiling
the product, this could damage the process being
controlled.

Model no.

Display height (PV)

Display height (SV)

AI-7481

0.30” 0.56”

0.80” 0.36”

0.36”

0.36”0.36”0.24”

0.39”

0.56”

AI-7881AI-7781 AI -79 81 AI -76 81

Fe-k(J) T/C

Cr-AL(K) T/C

Sensor Type

Accuracy

o

± 1 C

o

0 ~ 1700 C

o

0 ~ 1700 C

o

0 ~ 1800 C

o

-100 ~ 450 C

Resolution

Range

o

1 C

o

1 C

o

1 C

}

(R) T/C

(S) T/C

TC - N

TC - T

TC - B

Pt-100(RTD)

Pt-100(RTD 0.1)

o

0 ~ 760 C

o

-99 ~ 1300 C

o

-99 ~ 1300 C

o

-99 ~ 400 C

o

-99.9 ~ 450.0 C

o

1 C

o

1 C

o

1 C

o

1 C

o

1 C

o

0.1 C

o

± 0.3 C

OP1

PV

SV

TUNE

SET AT

-therm

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AI-7981

OP1

PV

SV

-therm

i

AI-7781

SET AT

AI-748 1

OP1

PV

SV

SET AT

SET

AT

PV

SV

AI-768 1

OP1

PV

SV

AI-788 1

OP1

SET

AT

1

OIM AI-7X81 V2.0 Page 1 of 6

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OVER ALL DIMENSIONS & PANEL CUT OUT (IN MM)

TABLE : 1

Model

Dim

48
72
96
96
48

48
72
96
48
96

8
10
10
10
10

75
65
45
45
45

44
68
92
44
92

44
68
92
92
44

9
9
9
9
9

A B

HC D F GE

43
66
89
89
43

AI-7481
AI-7781
AI-7981
AI-7681
AI-7881

MECHANICAL INSTALLATION

The label on the controller identifies the serial number, wiring connec tions and batch number.

INSTALLATION GUIDELINES :

1. Prepare the cut-out with proper dimension as shown in
Figure.

2. Remove clamp from controller

3. Push the controller through panel cut-out and secure
the controller in its place by tightening the side clamp.

C H

MODEL : AI - 7681

E

D

C

H

A

B

F

G

PANEL

CUTOUT

CAUTION: To prevent the risk of electrical shock, switch off the power before making/removing any connection or removing

the controller from its enclosure.

ELECTRICAL INSTALLATION :

The el ectri cal connection diagr am show n on the controller encl osure i s as below.

A

B D

E

G

F

MODEL:-AI-7481/7781/7981

PANEL

CUTOUT

MODEL : AI - 7881

B

A

E

D

C

H

G

F

PANEL

CUTOUT

4

5

6

7

1

2

3

AI - 7481

6 7

4

5

1

2

3

AI - 7781

6 7

4

5

1

2

3

AI - 7981

FRONT PANEL LAYOUT

1

2

4

3

6

7

5

AI - 7881

AI - 7681

1

5

3

2

6

4

7

AI - 7981

AI - 7681 / AI - 7881

AI - 7781

SUPPLY

L

N

1

2

3

4

5

6

7

8

9

10

11

12

15

16

13

14

NO NCCM

SSR

AI - 7481

SUPPLY

L

N

1

2

3

4

5

6

7

8 9

10

11

13

14

15

16

12

NO NCCM

SSR

1

2

3

4

5

6

10

11

12 13 14 15 16 17 18

7

8

9

NO NCCM

RELAY

RELAY

RELAY

SSR

SUPPLY

L

N

1

2

3

4

5

6

7

8

9

10

11

12 13 14 15 16 17 18

NO NCCM

RELAY

SSR

SUPPLY

L

N

OP1

PV

SV

TUNE

SET AT

-therm

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AI-7981

OP1

PV

SV

-therm

i

AI-7781

SET AT

AI-748 1

OP1

PV

SV

SET AT

SET

AT

PV

SV

AI-7681

OP1

PV

SV

AI-7881

OP1

SET

AT

Glows when OP1 is ON & flashes when delay time (dly1) is in operation(if selected mode is ON-OFF)

( ( (
along with UP k ey. (4) To scroll the pa ram ete r & to st ore i ts value.

1) For SP pro gramming. 2) To ac ces s C ontrol mod e. 3) To ac ces s Co nfi gur ati on m ode

( (
(with SET key ) . (3) To acknow led ge Ala rm. ( 4) To enter in tu ne mo de (w ith D OWN K ey).

1) To in crease/alt er param ete r val ue in program mode . 2 ) To Ente r in co nfi gur ati on mo de

( ( To ente r in tune m ode (wi th
UP Ke y).

1) To d ecr eas e / alter paramete r value in pro gram mo de. 2)

It will displ ay (1 ) Mea sur ed va lue of selecte d inp ut or E rro r massages in ru n mod e.
(2) Paramet ers Va lue in program m ode .

It will display (1) (Main s ) / SP2 ( Aux ili ary /Al arm) set value / Set Soa k tim e
value/ bala nce o r ela pse d soa k time in run mode . (2) P ara met er co de in program mo de.

SP et point

1

2

3

4

5

6

7

OP1 LED

UPPER

DISPLAY

LOWER

DISPLAY

SET
KEY

SHIFT

KEY

Sr.

NAME FUNCTION

UP

KEY

DOWN

KEY

(1) To in crease/alt er pa ram ete r val ue in program mo de wi th Up / D n Key.
(2) Press for 3 Sec i n Pro gra mmi ng this will hel p to go b ack t o pre vious parame ter.

FRONT PANEL LAYOUT DESCRIPTION :

2

OIM AI-7X81 V2.0 Page 2 of 6

Model no.

Weight (gms.)

AI-74 81 AI-77 81 AI-79 81 AI-78 81AI-76 81

130 200 240 200 200

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DELAY 1

0

to

500 Sec.

This parameter will be prompted only if selected control action is ON-OFF.
It sets the main output restart time where O/P once turned off will turn ON
only after restart time, regardless difference between PV & SP in Heat or
Cool mode. If set to '0', O/P will be switched without delay. Also, Delay will
be applicable in case of every power ON.

90 Sec.

CONTROL

HYS

o

1 to 25 C

This parameter will be prompted only if selected control action is ON-OFF.
It sets the dead band between ON & OFF switching of the Output. Larger
value of hysterisis minimize the number of ON-OFF operation to the load.
This increases life of actuators like contactors but, also produces large
errors (between PV & SV).

2°C

OUTPUT

OFF

1 to 10

This parameter will be prompted only if selected control action is PID.
With this parameter O/P will be Completely OFF after the Set Point +
Offset Value. If Disable, O/P will act Depending upon the PID Value
after Set Point achieved.

Disable

This parameter will be available only if Enabled in Configuration List.
User can set ramp rate/min for SP1 (Set Point) to minimize
overshoot.

RAMP
RATE

o

0.0 C
to

o

25.0 C

Disable

POWER UP :

At power on, f ol lo wi ng sequence will be prompted on the display for 1 sec. till it reaches to Home
display mode.

User can change SP value using UP/ DOWN keys. Holding the key, will
change the value at a faster rate. Press SET key to store the desired
value & move on to the next parameter.

o

0 C

LSPL ~ HSPL

CONTROL

SET

POINT

PROGRAMMING

USER LIST : To access the user list press SET key once.

LOWER

DISPL AY

UPPER

DISPL AY

PARA

METER

RANGE

DESCR IPT ION

DEFAULT

UPPER

DISPL AY

LOWER

DISPL AY

MODEL VERS ION INPUT HOME

PV

SV

LOWER

DISPL AY

UPPER

DISPL AY

PARA

METER

RANGE

DESCR IPT ION

DEFAULT

PROPORTIONAL

BAND

0.5

to

99.9°C

This parameter will be prompted only if selected control action is PID. It
sets bandwidth over which the output power is adjusted depending upon
the error (SV-PV). The value of this parameter is automatically set by Auto
tune function.

o

5.0 C

INTEGRAL

TIME

0

to

9999 Sec.

This parameter will be prompted only if selected control action is PID. It
sets the time taken by PID algorithm to remove steady state error. The
value of this parameter is automatically set by Auto tune function. If set to
‘0’, this function will be disabled.

240

DERIVATIVE

TIME

0

to

300 Sec.

This parameter will be prompted only if selected control action is PID. It
defines how strongly the controller will react to the rate of change of PV.
The value of this parameter is automatically set by Auto tune function. If
set to ‘0’, this function will be disabled.

60

CYCLE

TIME

0.5

to

100.0 Sec.

This parameter will be prompted only if selected control action is PID.
User can set this value based on process being controlled & type of
output being selected. For Relay O/P, cycle time should be more than
12sec & for SSR O/P, cycle time should be less than 10sec.

16.0 Sec.

0

Set this parameter to 15 (Default LOCK CODE) to access Control List.
User has a choice to set different Lock Code via USER LOCK CODE in
Config. List.

1 ~ 9999

LOCK
CODE

CONTROL LIST : SET & DOWN key simultaneously To enter in this mode, press for 3 sec. User can then set

the control parameters.

50 %

to

100 %

100 %

TUNE

OFFSET

This parameter will be prompted only if selected control action is PID.
This parameter allows the User to carry out Auto Tuning function below
set point.(If tune offset is 50 %, tuning will be carried out at 50 % of set
point and if 100 %, tuning will be carried out at 100% of the set point.)

100 %

OUTPUT
POWER

LIMIT

0.0 %
TO

100.0 %

This parameter will be prompted only if selected control action is PID.
This parameter will decide the Max. output power in % applied to the load.

3

OIM AI-7X81 V2.0 Page 3 of 6

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CONTROL

LOGIC

FOR O/P

HEAT

This parameter will be prompted only if selected control mode is ON-OFF.
User can select heating logic in which OP1 will remain ON till PV < SP.
(PV increases when output is ON.)

This parameter will be prompted only if selected control mode is ON-OFF.
User can select cooling logic in which OP1 will remain ON till PV > SP.
(PV decreases when output is ON.)

0

Set this parameter to 15 (Default LOCK CODE) to access Config. List.
User has a choice to set different Lock Code via USER LOCK CODE in Config. List.

LOCK
CODE

LOWER

DISPL AY

UPPER

DISPL AY

PARA

METER

DESCR IPT ION

DEFAULT

CONTROL

MODE

FOR O/P 1

PID

User can select between PID or ON-OFF action algorithm to be adopted for output.

INPUT

FILTE R

o

1 C

Controller is equipped with an adaptive digital filter which is used to filter out any
extraneous pulses on the PV. Filtered PV Value is used for all PV dependent
functions. If PV signal is fluctuating due to noise, increase the filter time constant
value.

PROCESS

VALUE

OFFSET

o

0 C

Function of this parameter is to add/subtract a constant value to the measured PV to
obtain Final PV for control applications. This parameter value needs to be altered for
one of the following reason :
(i) To compensate for known thermal gradient.
(ii) To match the display values with another recorder or indicator measuring the
same PV.

LOWER

SET

POINT

LIMIT

o

0 C

Sets the minimum limit for set point adjustment. It can be set from minimum
specified range of selected sensor to HSPL value.

HIGHER

SET

POINT

LIMIT

o

400 C

Sets the maximum limit for set point adjustment. It can be set from LSPL value to
maximum specified range of selected sensor.

Fe-k(J) T/C

Cr-AL(K) T/C

Pt-100(RTD)

Sensor Type

Accuracy

1

±o

C

o

0 ~ 760 C

o

-99 ~ 1300 C

o

-99 ~ 1300 C

o

-99 ~ 400 C

o

0 ~ 1800 C

o

-100 ~ 450 C

Resolution

Range

o

1 C

o

1 C

o

1 C

}

(R) T/C

(S) T/C

TC - N

TC - T

TC - B

Pt-100(RTD 0.1)

o

-100.0 ~ 450.0 C

o

0 ~ 1700 C

o

0 ~ 1700 C

o

1 C

o

1 C

o

1 C

o

1 C

o

0.1 C

o

1 C

o

0.3 C

±

TC - J

INPUT

TYPE

This parameter value is set according to the type of sensor (Thermocouple or RTD
input) connected to the controller's input terminals.

CONFIGURATION LIST : (1) key simultaneously To enter in this mode, press and hold SET & UP for 3 sec.

(2) Press UP or DOWN key to scroll between parameter options.
(3) Press SET key to store the current parameter & move on to the next parameter.

4

OIM AI-7X81 V2.0 Page 4 of 6

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OUTPUT

TYPE

RELAY

User has to set this parameter very carefully in accordance with the output used.
(Separate terminal for RELAY & SSR, Refer electrical installation )
Select Relay if LOAD is connected via contactor. Whenever user selects Relay, Cycle
time will automatically get set to 16 sec. User can modify cycle time via control list.

Select SSR if LOAD is connected via SSR (DC voltage pulses). Whenever user
selects SSR, Cycle time will automatically get set to 1sec. User can modify cycle
time via control list.

OVERSHOOT

CONTROL

POINT

DISABLE

This parameter will be prompted only if selected control action is PID. Setting this
parameter on higher side will proportionally slows down the rate of rise of PV to
minimize overshoot(this may cause delay to reach SP). Setting on lower side will
proportionally or disabling this parameter will increase the rate of rise of PV( which
may cause overshoot). Disable this option if delay is not required to reach SP.

PARA
METER

DESCRIPTION

DEFAULT

This function will be executed only if selected control action is PID & Auto tune is
Enable.
Auto-tuning function can be initiated by setting this parameter to ‘YES’. The decimal of
LSB flashes till Auto Tuning function is in progress. During Auto-tuning, Controller
learns the process characteristics by itself & calculates required P, I & D values.
User can cancel or abort this feature by setting this parameter to ‘NO’.

AUTO

TUNING

MODE

NO

LOWER

DISPL AY

LOWER

DISPL AY

UPPER

DISPL AY

UPPER

DISPL AY

PARA

METER

DESCR IPT ION

DEFAULT

AUTO TUNING MODE : To enter in this mode, Press & hold SHIFT key for minimum 3 sec.

15

Default USER LOCK CODE is 15 to access Control & Configuration List.
User has a choice to set its own USER LOCK CODE between 1 to 9999, this is to
prevent unauthorized access of Control & Configuration List.

USER
LOCK
CODE

AUTO
TUNE

Enable

If Disabled, this parameter will not be prompted if user press Up & Down keys
Simultaneously for 3Sec.

SET

POINT 1

Enable

If Enabled, User can View & edit the Set point in USER list.

If disabled, User can only View the Set Point but Can not edit it in USER list.

This parameter will be prompted only if selected control action is PID.
If Enabled, this parameter will be prompted if user press Up & Down keys
Simultaneously for 3Sec.

5

OIM AI-7X81 V2.0 Page 5 of 6

RAMP
RATE

Disable

This parameter will be prompted only if OCP (over shoot control point) is disabled.
When enabled, User can set the desired RAMP rate in USER list.

When disabled, this parameter will not be prompted in USER list.

Toggle

This parameter will be prompted only if RATE (Ramp Rate) is Enabled.
By pressing DOWN key, Lower display will Toggle between Actual Set point Value
i.e. Target Set Point (T-SP) & Ramping Set point (R-SP).

By this parameter Lower display will only show the Target Set Point T-SP Value.

By this parameter Lower display will only show the Ramping Set Point R-SP.

LOWER

DISPLAY

MESSAGE

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6

OIM AI-7X81 V2.0 Page 6 of 6

Innovative Instruments

On

Google Play

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Build ing N o.2, Link Ro ad, M alad (W), Mu mba i - 400064.
Tel: [phone];
E-mai l :
Website :

sales @in novative ins truments .co .in

www.in novative ins truments .co .in

Mfgd by: Innovative Instruments & Controls LLP

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NC : Normally Close terminal of
Relay
NO : Normally Open terminal of
Relay
OP1 : Output 1
PV : Process Value (actual temp.)

C.A. : Control Action
CJC : Cold junction compensation
CM : Common terminal of relay
LWC : Lead wire (Length)
compensation

SP : Set Point Value(set temp.)
SSR : Solid State Relay
T/C : Thermocouple

ABBREVIATION :

Adjus t

Proportional Band

Integral Time

Derivative Time

Slow Response
Over Shoot or Oscillations
Slow Response
Instability or Oscillation
Slow Response or Oscillation
High Over Shoot

Decrease PB
Increase PB
Decrease Int
Increase Int
Decrease Dt
Increase Dt

Sympt om

Solut ion

Fig: 3.1

HEAT LOGIC / ON-OFF

TIME

0

TEMP ( C)

HYSTERISIS

SP

ON ON ON

AMB

O/P

OFF OFF

Fig: 3.2

TIME

COOL LOGIC / ON OFF

O/P

O/P

0

TEMP ( C)

AMB

HYSTERISIS

ON ON ON

SP

OFF OFF

ON-OFF ACTION : In this mode, Output (Relay/SSR) remains ON till actual temperature reaches to the set point value. On

reaching SP, Output turns OFF & remains OFF till actual temperature drops down (in Heat logic) or raises (in Cool logic)
equal to hysterisis set by User. (As shown in Fig : 3.1 & 3.2)

USER GUIDE :

AUTO TUNING MODE : In this mode, Controller learns the process characteristics by itself and calculates the required P,I &

D values. It can be performed at any time after power ON but, it is best to start it when the process is at Ambient temperature
in order to minimize overshoot & undershoot. Auto tuning is applied in case of :
(1) Initial set up for a new process.
(2) Substantial change in SP from previous auto tuning value.
(3) Control accuracy is not satisfactory.
If the control performance by using auto-tuning is still unsatisfactory, User can apply the further adjustments of P,I & D values
as shown below