Extech Instruments 48VTR User manual

User's Guide
Digital Process Controller
Model 48VTR
-PV-
-SV-
1
00
OUT ALM
VTR

Model 48VTR - Version 5.0 – January 2006
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
Support line [phone]
Technical support: Extension 200; E-mail: [email protected]m
Repair & Returns: Extension 210; E-mail: [email protected]
Product specifications subject to change without notice
For the latest version of this User’s Guide, Software updates, and other
up-to-the-minute product information, visit our website: www.extech.com
Extech Instruments Corporation, 285 Bear Hill Rd., Waltham, MA 02451
Warranty
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects
in parts and workmanship for one year from date of shipment (a six month limited warranty
applies to sensors and cables). If it should become necessary to return the instrument for
service during or beyond the warranty period, contact the Customer Service Department at
[phone] ext. 210 for authorization or visit our website www.extech.com for contact
information. A Return Authorization (RA) number must be issued before any product is
returned to Extech. The sender is responsible for shipping charges, freight, insurance and
proper packaging to prevent damage in transit. This warranty does not apply to defects
resulting from action of the user such as misuse, improper wiring, operation outside of
specification, improper maintenance or repair, or unauthorized modification. Extech
specifically disclaims any implied warranties or merchantability or fitness for a specific
purpose and will not be liable for any direct, indirect, incidental or consequential damages.
Extech's total liability is limited to repair or replacement of the product. The warranty set
forth above is inclusive and no other warranty, whether written or oral, is expressed or
implied.
Calibration and Repair Services
Extech offers repair and calibration services for the products we sell. Extech also
provides NIST certification for most products. Call the Customer Service Department for
information on calibration services available for this product (refer to the phone, email,
and website information in the support box provided below). Extech recommends that
annual calibrations be performed to verify meter performance and accuracy.
Technical Support
To contact Technical Support, refer to the phone, email, and website information in the
support box provided below.
Before contacting Extech, please have the following information handy:
•Detailed description of concern
•Current settings of the programming menu levels 1 through 4
•Wiring diagram of the controller and the process to which the controller is
connected
•Operator’s manual
•Error messages from controller’s display (if any)
Copyright ©2006 Extech Instruments Corporation
All rights reserved including the right of reproduction in whole or in part in any form.

Model 48VTR - Version 5.0 – January 2006
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Table of Contents
Warranty . . . . . . 2
Calibration and Repair Services . . . 2
Technical Support . . . . . 2
48VTR Overview . . . . . 4
Specifications . . . . . 5
Front Panel Description . . . . 7
Mounting . . . . . . 7
Wiring . . . . . . 8
Control Output Descriptions . . . . 10
Display Descriptions . . . . . 13
Keypad Descriptions . . . . . 14
Programming Menu Levels . . . . 15
Calibration . . . . . . 20
Automatic Tuning . . . . . 21
Auto / Manual Control . . . . 22
Ramp-to-Setpoint Limit . . . . 22
Soak and Event Timers . . . . 23
Appendix A: Alarm Functions . . . . 24
Appendix B: Application example . . . 25

Model 48VTR - Version 5.0 – January 2006
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Controller Overview
Controller Wiring
The controller must be wired before use. The controller’s input, outputs, and AC power are
connected via its rear terminals. Refer to the Wiring Section for details.
Programming Menus
The controller has four (4) Programming Menu Levels. Each menu includes a series of
parameters that customize the controller to meet the user’s needs. The menu structure and
parameter descriptions are detailed in the Programming Menu Levels Section. Check the
factory default settings for each parameter and only change a setting if necessary.
Inputs
The controller accepts an input from a Thermocouple, RTD, or Analog signal. Wire the
input as shown in the Mounting and Wiring Section. The measurement (PV for Process
Variable) is displayed on the controller’s top LED readout in red.
Setpoint Value (SV)
The Setpoint Value (SV) is the target value. For example, in an oven application the
desired oven temperature is the SV. This SV is changed using the front panel up/down
arrow keys. The SV is shown on the controller’s lower LED display digits in green.
Control Output
The control output is wired to an external control device such as a heater, valve, or switch.
See the Mounting and Wiring Section for details. The controller automatically controls an
external device to bring the Process Variable (PV) in line with the Setpoint Variable (SV).
Available outputs are Relay, DC trigger, and Analog Output.
Tuning
The controller must be tuned for every new application. Run the Automatic Tune function
after the controller is wired and ready to go. The Auto Tune function matches the response
of the controller to the characteristics and dynamics of the process it is controlling. Refer to
the Auto Tuning Section for details on automatic tuning. Although auto tuning will be
sufficient in most cases, there may be times when manual adjustments are required.
Qualified personnel can Manually Tune the controller using the PID parameters in the 2nd
Menu Level. Note that improper tuning can cause sever process disturbances. Always use
Auto Tuning when possible.
Alarm Output
The controller has one alarm output relay that can be used to switch on a light, sound a
buzzer, shut down a heater, etc. at a programmed alarm setpoint. A list of alarm functions
can be found in Appendix A. Use the ‘A1Fu’ parameter in the third programming level to
set the desired alarm type. Use the ‘A1SP’ parameter in the 1st Menu Level to set the
alarm setpoint.
Alarm Timers
The Alarm relay can be used as an EVENT or a SOAK timer. An Event Timer switches the
Alarm relay ON or OFF based on certain process condition. The SOAK timer allows the
controller to hold a desired Setpoint (SV) for a programmed period of time before switching
off. Refer to Appendix ‘A’ and the Soak/Event Timer Sections for details.
System Reset
To revert all of the parameters to their original factory default settings, press and hold the
UP and DOWN arrow keys simultaneously while turning the controller ON. Release the
keys after the self-test (when the display shows ‘8888’).
Locking Out the Controller
To lock out the controller, in order to avoid setpoint and program tampering, refer to the
‘REMO’ and ‘PARAMETER LOCK’ (PL) parameters in the 3rd Programming Level.

Model 48VTR - Version 5.0 – January 2006
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Specifications
General Specifications
Display Dual 7-segment 4-digit LED: Red digits for Process Variable
(PV) and green digits for Setpoint Variable (SV)
Display range -1999 to 9999
Indicating accuracy ± (0.2% full scale + 1 digit)
Display update rate 4 readings per second
Output status indication Front panel Alarm (ALM) and Control (OUT) output LED lamps
inform user when an output switches on or off.
Out-of-range indication PV display blinks.
No input indication PV displays ‘OPEN’ when input terminals are disconnected.
Auto Tune indication Right-most decimal on the PV display flashes while the
controller is in the auto tune mode.
Calibration data Stored in non-volatile memory along with user parameter edits.
Meter construction Case is ABS plastic and the front panel is drip- and dust-proof
Lexan (NEMA and IEC IP55 equivalent)
Power supply requirement 90 to 264VAC 50/60Hz (controller automatically
accommodates any voltage between 90 to 264VAC)
Power consumption 6 Watts
Insulation Resistance > 50MΩ
Noise rejection Common Mode: 110 dB; Normal Mode: 50 dB (typical)
Operating conditions 14 to 122oF (-10 to 50oC); 90% Relative Humidity max.
Storage temperature -4 to 140oF (-20 to 60oC)
Panel cut-out dimensions 1.77 x 1.77" ±0.02" (45.0 x 45.0mm ±0.5mm)
Thermocouple Input Specifications
Thermocouple (TC) types J, K, T, E, B, R, S, and N (user programmable)
TC Break protect Upscale and Downscale
Lead wire effect 0.015% / ohm
Input impedance > 10MΩ
Repeatability 0.83oC
Temperature stability 5uV/oC typical
TC Ranges Type K: -58 to 2498oF (-50 to 1370oC)
Type J: -58 to 1830oF (-50 to 1000oC)
Type B: 32 to 3272oF (0 to 1800oC)
Type T: -454 to 752oF (-270 to 400oC)
Type E: -58 to 1382oF (-50 to 750oC)
Type R: 32 to 3182oF (0 to 1750oC)
Type S: 32 to 3182oF (0 to 1750oC)
Type N: -58 to 2372oF (-50 to 1300oC)

Model 48VTR - Version 5.0 – January 2006
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RTD Input Specifications
RTD type Platinum 100Ω(DIN and JIS)
RTD range -392 to 932oF (-200 to 500oC)
Break protection Up- and down-scale
Lead wire effect 0.015o/ Ohm
Repeatability 0.2oC
Analog (Linear) Input Specifications
Current Input 4 to 20mA DC (2.7Ωinput impedance)
Voltage Input 1 to 5V DC (>10MΩinput impedance)
Display range -1999 to 9999 digits
Repeatability Within 1 digit
Relay and DC Trigger Control Output Specifications
Relay output SPDT, dry contact, form C relay contact can switch up to 5
Amps @ 110V AC or 24VDC (Note: For Resistive Loads)
DC trigger (pulse) output 24V DC (DC drive for external SSR)
ON: 24V DC typical, 29V DC max; OFF: 0.3V DC max
Control actions Indirect acting (heating) and direct acting (cooling)
Control types ON/OFF control with Hysteresis (deadband)
Time proportioning control (for relay or pulsed DC output)
Standard proportional output (analog output)
Automatic tuning Push-button activation. Automatically tunes the controller’s
proportional band and integral/derivative times.
Manual Tuning Proportional Band (Pb): 0.0 to 100.0% of Full Scale
Integral time or ‘Reset’ (Ti): 0 to 3000 seconds
(includes anti-reset wind-up)
Derivative time or ‘Rate’ (Td): 0 to 3000 seconds
Cycle Time: 1 to 100 seconds (set to ‘0’ for 4-20mA output)
Hysteresis: 0.0 to 25.5% of Full Scale
ALARM Output Specifications
Alarm relay output SPST, dry contact relay can switch up to 3 Amps @ 110VAC;
(Note: For Resistive Loads only)
Alarm modes Deviation and Absolute Alarms with deadband adjustment.
Alarm relay can also be used with the controller’s Soak/Event
Timer functions.
ANALOG Output Specifications
Analog output 4-20mA DC
Load limit 600Ωmax.
Programming Set Cycle Time (Ct) to ‘0’ to enable the analog output

Model 48VTR - Version 5.0 – January 2006
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-PV-
-SV-
1
00
OUT ALM
VTR
Front Panel Description
•Process Variable (PV) Display: RED display digits represent actual measurement
•Setpoint Variable (SV) Display: GREEN display digits represent desired value
•Control Output (OUT) status LED: When output is ON the LED next to OUT switches ON
•Alarm Output (ALM) status LED: When alarm output is ON the LED next to ALM switches ON; also blinks
when an Alarm Timer is counting down (see the EVENT/SOAK Timer section).
•Push-buttons (explained in Display and Keypad Description section):
'Return' Programming Key
DOWN Arrow Programming Key
UP Arrow Programming Key
'Scroll' Programming Key
Mounting
1. Prepare a 1.77 x 1.77" ±0.02" (45 x 45mm ± 0.5mm) panel cutout. Note that the panel
may be up to 0.4" (10mm) thick.
2. Remove the plastic mounting bracket and slide the meter into panel through the
cutout.
3. Replace the mounting bracket and then tighten the bracket screws. Do not tighten the
mounting screws excessively.

Model 48VTR - Version 5.0 – January 2006
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Wiring
AC Power Wiring
The AC supply terminals (6 and 7) accept 90 to 264VAC 50/60Hz without having to be
physically switched or specially configured. Do not connect the controller to a live power
source until all wiring, explained below, is correct.
Thermocouple Input
For a thermocouple input use terminal 1 (negative) and terminal 2 (positive).
Analog Input (4-20mA)
For an analog input, use terminal 1 (negative) and terminal 2 (positive).
RTD Input (2, 3, or 4 wire)
RTD inputs use terminals 1, 2, & 3. Select a scheme from one of the diagrams below.
6 7 8+ 9- 10
1- 2+ 3 4 5
90 to 264VAC
N.O. Control Relay
Analog, or pulse
DC Trigger Output
N.C. Control
Relay
2, 3, or 4-wire
RTD Input
Thermocouple
or Analog Input
48VTR
Rear Terminal Designations
Please refer to the accompanying
paragraphs for actual wiring instructions
N.C. Alarm
Relay
RTD Input Wiring
123
Jumper
2-wire RTD Input
123
3-wire RTD Input
123
4-wire RTD Input

Model 48VTR - Version 5.0 – January 2006
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Control Output Relay Wiring
The control relay is accessed via terminals 8, 9, and 10. Terminals 8 and 9 constitute a
normally closed switch; terminals 8 and 10 constitute a normally closed switch. When
the controller activates the relay, the normally open and normally closed switches
change state. The relay itself does NOT provide its own power. AC power is wired as
shown in the wiring example below.
Pulsed DC Trigger Output Wiring
The pulsed DC Trigger output delivers 0VDC to 29VDC (approx.) from terminals 8
(positive) and 9 (negative).
Analog (4 to 20mA) Output Wiring
The 4 to 20mADC output is available on terminals 8 (positive) and 9 (negative). For
proper operation of the analog output, set parameter Ct (in 3rd Menu Level) to ‘0’.
Alarm Relay Output
The Alarm Relay is a normally open (N.O.) switch available at terminals 4 and 5. Relays
themselves do NOT supply power, power must be supplied; wire the relay as shown in
the diagram.
Normally Open (N.O.) Relay contacts
89
Control Device
i.e., Heater, Valve,
Pump, Switch, etc.
External
Power
Source
Normally Closed (N.C.) relay contacts
810
Control Device
i.e., Heater, Valve,
Pump, Switch, etc.
External
Power
Source
Control Output Wiring
Alarm Output Wiring
Normally Open (N.O.) Relay contacts
Alarm Device
i.e., buzzer, indicator,
siren, cut-off switch,
etc.
45
External
Power
Source

Model 48VTR - Version 5.0 – January 2006
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Control Output Descriptions
Relay Output Control
The control relay is a mechanical single-pole double-throw form ‘C’ contact that has only
two states, ON and OFF. Wire the relay as described in the Wiring Section. In order to
overcome the limitations of ON-OFF control (setpoint overshoot and oscillations, droop,
inefficiency, etc.) a technique called TIME PROPORTIONING is employed. ‘ON-OFF’ &
‘Time Proportioning’ methods are described below.
ON-OFF Control
This is the simplest form of control. For a heating application, the controller’s output is
100% (ON) when the PV < SV and 0% (OFF) when PV > SV. For cooling applications,
the output is 100% (ON) when PV > SV and 0% (OFF) when PV < SV. To program the
controller for ON-OFF control, set the ‘Pb’ parameter in the 3rd Menu Level to ‘0’.
Time Proportioning Control
To program the controller for Time Proportioning control, run Auto Tune per the
instructions in the Auto Tuning section. The only parameter that must be manually set is
the CYCLE TIME parameter in the 3rd Menu Level. Cycle Time and Time Proportioning
Control can best be explained through example. Refer to the diagrams below and the
explanation that follows.
DIAGRAM 1 DIAGRAM 2
DIAGRAM 3
ON-OFF HEATING APPLICATION
SV
PV ABOVE SV
OUTPUT = 0%
PV BELOW SV
OUTPUT = 100%
PV
PV
ON-OFF COOLING APPLICATION
SV
PV ABOVE SV
OUTPUT = 100%
PV BELOW SV
OUTPUT = 0%
PV
PV
10% Output = ON 1 seconds; OFF 9 seconds
for a 10-second CYCLE TIME (Ct)
TIME (in seconds)
0 2.5 5 7.5 10
ON RELAY OFF
50% Output = ON 5 seconds; OFF 5 seconds
for a 10-second CYCLE TIME (Ct)
TIME (in seconds)
0 2.5 5 7.5 10
RELAY ON RELAY OFF
80% Output = ON 8 seconds; OFF 2 seconds
for a 10-second CYCLE TIME (Ct)
TIME (in seconds)
0 2.5 5 7.5 10
RELAY ON OFF

Model 48VTR - Version 5.0 – January 2006
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The CYCLE TIME (Ct in 3rd Menu Level) dictates how often the controller makes an output
percentage change. For the above diagrams, the Ct = 10, therefore every 10 seconds the
controller adjusts the output percentage. The controller decides the output percentage
based on the proximity of the PV to the SV. The further the PV is from the setpoint, the
higher the percentage. The closer the PV is to the setpoint, the lower the percentage.
Three Cycle Time examples are shown in the diagrams.
In Diagram 1 (above), the controller is calling for an output of 80% power. This is because
the process variable (PV) has a long way to go to get to the setpoint (SV). So, in this case,
for the 10-second cycle time period, the output will be ON for 8 seconds (80% of the 10-
second cycle time), and OFF for 2 seconds. In Diagram 2, we’re much closer to the SV
and controller supplies 50% power. The output will be ON for 5 seconds and OFF for 5
seconds. In Diagram 3, the PV is very close to setpoint so the output power is now 10%
power. Output is ON for 1 second and OFF for 9 seconds.
The cycle time setting is critical and must be set to the longest time possible without
causing process oscillations. The longer the Cycle Time the longer the relay life span.
DC Trigger Output Control
Read the above paragraphs for ON-OFF and Time Proportioning Control actions since the
DC trigger operates in the same fashion. The only difference between a relay output and a
DC trigger output is that the DC trigger supplies its own power (available on terminals 8
and 9). The relay, on the other hand, must be wired in series with an AC source to produce
power. The DC trigger output is approx. 0VDC for 0% power and 29VDC (max) for 100%
power. Wire the DC trigger as described in the Wiring section of this manual. Caution:
When a DC trigger output is installed in the controller, never connect AC voltage to
terminals 8 or 9.
Analog Output Control (4 to 20mA)
With an analog output, the amount of current that the controller outputs depends on the
proximity of the PV to the SV; the further the PV is from the setpoint, the higher the current
output. As the PV approaches the SV the current output decreases. 100% output = 20mA,
0% output = 4mA, 50% output = 12mA, and so on. For proper operation of an analog
output, Cycle Time (parameter Ct in the 3rd Menu Level) must be set to ‘0’.
Controller Output% vs. Proportional Band (Pb) Setting
The 48VTR output percentage is largely determined by the proximity of the PV (Measured
variable) to the SV (Setpoint). However, the Proportional Band and the High/Low Limit
settings also have an effect on the Controller Output.
When the Proportional band is set to a small number (narrow band), the output gain is
higher - meaning that the process is allowed to rise to setpoint rather quickly. When the
Proportional band is set to a large number (wide band), the output gain is lower - meaning
that the process is restricted from rising to setpoint too quickly. Every process is different
and the Proportional Band must be set to match the characteristics of each individual
application. Auto Tune is the best way to do this. In the example diagrams below, a WIDE,
a NARROW, and a CORRECT Proportional Band are illustrated.
The HIGH and LOW LIMIT parameters (HiLt and LoLt in the 3rd Programming Level) are
also important since the Proportional Band size is dependent on the size of the SPAN
(High Limit minus Low Limit). For example, a 10% Proportional Band setting with a wide
SPAN is larger than a 10% Proportional Band setting with a narrow SPAN.
Note that in the example diagrams below, the controller’s are configured for HEATING
(selection 1 under Act in the 3rd Menu Level). For COOLING, the PV would be approaching
the SV from above.
NOTE: ‘Pb’ (Proportional Band) is automatically set when the Auto Tune function is used.
Refer to the section on Auto Tuning for details. ‘Pb’ can also be manually adjusted.

Model 48VTR - Version 5.0 – January 2006
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Pb setting too narrow
When a Proportional Band is set too
narrow, the PV rises too quickly and
typically overshoots the SV as shown.
Pb setting too wide
When a Proportional Band is set too
wide, the PV rises too slowly and may
never reach the SV.
Pb set correctly
When the Proportional Band is set
correctly, the PV rises to the SV in a
reasonable amount of time with little
undershoot. A slight oscillation of the PV
(within specification) is typical once the
SV is reached.
SV
P
R
O
C
E
S
S
V
A
R
I
A
B
L
E
TIME
Output throttles
between 0 and 100%
in the Pb region
0% Output Region
100% Output Region
Desirable slow oscillation of
PV around SV
Pb
Region
Proportional Band (Pb) set correctly
SV
P
R
O
C
E
S
S
V
A
R
I
A
B
L
E
TIME
Output throttles
between 0 and 100%
in the Pb region
0% Output Region
100% Output Region
PV undershoots SV
Pb
Region
Proportional Band (Pb) set too wide
SV
P
R
O
C
E
S
S
V
A
R
I
A
B
L
E
TIME
Output throttles
between 0 and 100%
in the Pb region
0% Output Region
100% Output Region
PV overshoots SV
Pb
Region
Proportional Band (Pb) set too narrow

Model 48VTR - Version 5.0 – January 2006
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Display Descriptions
Process Variable (PV) Display
•During normal operation, the top LED (red digits) displays the actual process
measurement (temperature, voltage, or current input signal). This process measurement
is known as the "Process Variable" or PV.
•When the user accesses one of the four programming levels, the red LED digits show
the currently selected parameter.
•The red LED digits also display controller error messages. Controller programming and
error messages are explained later in this section.
Setpoint Variable (SV) Display
•During normal operation, the bottom LED (green) displays the user-programmable
Setpoint Variable (SV). This represents the target to which the controller's output will
adjust the process. To adjust the Setpoint, use the up/down arrow keys.
•Note that the Setpoint cannot be adjusted higher or lower than the high and low limit
parameters programmed in Menu Level 4.
•While programming the controller, this green LED display shows the current setting for
the currently selected parameter (shown on the red LED digits). For example if the red
LED is displaying input type (type), the green LED shows the current selection. The user
could then use the up/down arrow keys to scroll to, and select, the desired input type.
Display Status Indicators
'ALM' Status Indicator (Alarm Relay Status LED)
This red LED is lit when the Alarm relay is active. Also, this LED flashes when the Alarm
is configured as an Event/Soak timer and is in the process of counting down. Refer to
the dedicated section on Soak and Event Alarm Timers and also Appendix ‘A’ for more
on Alarm/Timer functions.
'OUT' Status Indicator (Control Output Status LED)
This green LED switches on when the control output is active.
AUTO TUNE Status Indicator
When the controller is Auto Tuning, the rightmost decimal point on the green LED
display will flash. When the meter is finished tuning, the decimal point will stop flashing.
Auto Tuning may take from several minutes to several hours depending upon the
process in question. Refer to the Auto Tuning section for more information.
PV Display Error Messages:
AdEr: A/D converter is inoperable. Unit must be repaired or replaced.
Flashing PV: Over range condition with regard to input signal.
OPEN: Input sensor not connected or is inoperable.

Model 48VTR - Version 5.0 – January 2006
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Keypad Descriptions
SCROLL Key
•Press SCROLL once to access the 1st Menu Level, and then use the SCROLL key
again to move from one parameter to the next.
•The SCROLL key is also used in combination with the RETURN key to move
between menu levels (press both keys simultaneously for 5 seconds to move from
one menu level to the next). As the user scrolls through the menu items, the red
LED display shows the current parameter.
•Also, the SCROLL key is used to activate an Auto Tuning session (press and hold
the SCROLL key for 5 seconds to start an Auto Tuning session – Refer to the Auto
Tune Section for more information).
UP Arrow Key
The UP key increases the Setpoint (SV). Also, the UP arrow key is used to select items
from the lists in the programming menus.
DOWN Arrow Key
The DOWN key decreases the Setpoint (SV). Also, the DOWN arrow key is used to
select items from the lists in the programming menus.
RETURN KEY
•During normal operation, pressing the RETURN key permits the user to view the
controller output action as a percentage (0.0-100.0%). Press and hold the RETURN
key for 5 seconds to enter “manual mode” (refer to the Auto / Manual Control
section).
•Press this key from any other mode to return to the normal SV display.
•The RETURN key is also used with the SCROLL key (pressed simultaneously) to
move from one programming menu to another.

Model 48VTR - Version 5.0 – January 2006
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Programming Menu Levels
The 48VTR has four (4) Menu Levels used for programming. The Menu Levels are shown
in the Table below. Each parameter is described in detail in the following sections.
Menu Levels and Parameters
1st Menu Level 2nd Menu Level 3rd Menu Level 4th Menu Level
RAmp (0.0) Pb (0) REmo (0) LoCA (0.0)
SPoF (0.0) Ti (240) P-L (4) HiCA 1000
A1SP or timE Td (40) A1FU (2) TunE (1)
A1HY (0.1)
Act (1)
Unit (*)
Dp (*)
Ct (15)
HYST (0.1)
EroP (2)
Addr (0)
PvoF (0.0)
TYPe (*)
LoLt (0.0)
Note: In this Table, the default values are
shown in parenthesis. Parameters with an
asterisk * vary depending on the input type of
the controller (TC, RTD, or Analog input)
System Reset
To revert all of the parameters to their original
factory default settings, press and hold the UP and
DOWN arrow keys simultaneously while turning the
controller ON. Release the keys after the self-test
(when the display shows ‘8888’).
HiLt (500.0)
First Programming Menu Level
•Press the SCROLL key to enter the first level
•Then use the SCROLL key to move through the parameter list
•Use the ARROW keys to change a setting
•To return to normal operation at any time, press the RETURN key once
•The 1st Menu Level parameters are shown below:
rAmp Programmable rate of rise limit for PV. The ramp restricts the rate at which the
measured variable (PV) changes (Range: 0.0 to 100.0 units per minute). For more
details refer to the ‘Ramp to Setpoint’ Section later in this manual.
SPoF Setpoint Offset (Manual Reset). The setpoint can be offset by 0.0 to 100.0% of its
displayed value. For example, with a 10% setting, the controller's setpoint will be
10% higher than its displayed value. Therefore, if the Setpoint is displayed as 50,
the actual Setpoint would be 55 (10% of 50 is 5; 50 + 5 = 55).
A1SP Alarm Setpoint value. (First, set the Alarm type in the ‘A1Fu’ parameter; refer to
Appendix ‘A’ for Alarm functions). Allowable setting range is limited by the Low
and High Limit settings (3rd Menu Level) and the input type selected. To lock out
‘A1SP’, press the SCROLL and DOWN keys simultaneously for 4 seconds. To
unlock, press SCROLL & UP simultaneously for 4 seconds.
timE Programmable duration for the Event/Soak Alarm Timers. The range is 0 to 9999
minutes. Refer to the ‘Event/Soak Timers’ Section and Appendix ‘A’ for details.
Note: The Parameter Lock setting (P-L) can lock out certain levels and parameters. Some of the
above parameters may not appear depending on the P-L setting

Model 48VTR - Version 5.0 – January 2006
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Second Programming Menu Level
Press and hold the SCROLL and RETURN keys simultaneously to enter this level from
the first programming level. To return to normal operation at any time, press the
RETURN key.
NOTE: This is the Manual Tuning programming level. Rather than attempting to manually tune the
controller, it is strongly recommended that AUTO TUNING be employed. Auto Tuning automatically sets
the tuning parameters. Refer to the Auto Tuning Section for instructions. Improper use of the tuning
parameters can cause severe process disturbances. Only personnel familiar with manual tuning should
attempt to adjust the parameters in the second menu level. Manual tuning is beyond the scope ofthis
user guide.
Pb Proportional Band. Setting range from 0.0 to 100.0% of controller's Span. The
controller’s span equals the HiLt (high limit) minus the LoLt (low limit). High and
Low Limit parameters can be found in the 3rd Menu Level.
Default = 10.0%. Set Pb to 0.0% for ON/OFF control action. This value is
automatically calculated by activating the AUTO TUNE function
ti Integral (Reset). 0 to 3000 seconds setting range. Default = 240. This value is
automatically calculated by activating the AUTO TUNE function.
td Derivative (Rate). 0 to 3000 seconds setting range. Default = 40. This value is
automatically calculated by activating the AUTO TUNE function.

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Third Programming Menu Level
Press and hold the SCROLL and RETURN keys simultaneously for 5 seconds to enter
this level from the second programming level. To return to normal operation at any time,
press the RETURN key.
rEmo The rEmo (remote control) parameter, intended for use on the 96VTR, can be
used by the 48VTR to lock out all of parameters. Set to ‘1’ to lock out the
entire controller. Set to ‘0’ for full access.
P-L Parameter Lock. This security feature locks out selected programming levels
or single parameters thereby prohibiting tampering and inadvertent changes.
In the Table below, the user settings are listed on the left and the effect of the
setting on each Menu Level is shown on the right: To lock out the entire
controller, see the ‘rEmo’ parameter directly above.
Setting Menu 1 Menu 2 Menu 3 Menu 4
0 Displays A1SP* only Unlocked Unlocked Unlock
1 A1SP and rAmp only Unlocked Unlocked Unlocked
2 A1SP and SPoF only Unlocked Unlocked Unlocked
3 Unlocked (all shown) Unlocked Unlocked Unlocked
4 Displays A1SP only Unlocked Unlocked Locked
5 A1SP and rAmp only Unlocked Unlocked Locked
6 A1SP and SPoF only Unlocked Unlocked Locked
7 Unlocked Unlocked Unlocked Locked
8 Displays A1SP only Unlocked Only P-L can be changed Locked
9 A1SP and rAmp only Unlocked Only P-L can be changed Locked
10 A1SP and SPoF only Unlocked Only P-L can be changed Locked
11 Unlocked Unlocked Only P-L can be changed Locked
12 Displays A1SP only Locked Only P-L can be changed Locked
13 A1SP and rAmp only Locked Only P-L can be changed Locked
14 A1SP and SPoF only Locked Only P-L can be changed Locked
15 Unlocked Locked Only P-L can be changed Locked
* ‘A1SP’ and ‘TIME’ in the 1st Menu Level are mutually exclusive. ‘A1SP’ appears only if the ‘A1Fu’ parameter in the 3rd
Menu Level is set between 00 and 07 inclusive; ‘time’ appears only if ‘A1Fu’ is set between 08 and 11 inclusive.
A1Fu Alarm/Timer Function. Select the desired Alarm or Timer function from the
alarm/timer function list in Appendix ‘A’.
A1HY Hysteresis for Alarm. The Setting range is 0.0 to 25.5% of the controller's
‘Span’. Hysteresis is used to eliminate relay "chatter" by creating a ‘deadband’
region where no relay action can occur. The deadband extends equally above
and below the alarm setpoint. The larger the number set here, the larger the
deadband region.
Note: ‘Span’ is the meter’s region of operation extending from the 'LoLt' (low
limit) to 'HiLt' (high limit). Low and High Limit parameters can be found in the
3rd Menu Level.

Model 48VTR - Version 5.0 – January 2006
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Act Output control action. Set to "0" for cooling (direct) action or "1" for heating
(reverse/indirect) action.
unit Unit of measure selection. Program as follows:
0 degrees F
1 degrees C
2 Process analog inputs
dP Decimal Point selection.
00 no decimal point
01 0.1 resolution
02 0.01 resolution (for use with analog inputs only)
03 0.001 resolution (for use with analog inputs only)
Ct Cycle Time for relay output. Range: 0 to 100 seconds. This is the period of
time the controller waits between output changes. The longer the time, the
less responsive the controller will be to process changes. Set Ct for the
longest period of time possible without causing process oscillations; this will
help to prolong the life of the relay.
NOTE: Set ‘Ct’ to '0' seconds for the 4-20mA analog output option. Parameter
'Ct' is not used when ON/OFF control is used.
Hyst Hysteresis for ON/OFF control output. Users can create a deadband region
from 0.0 to 25.5% of SPAN. Hysteresis is used to eliminate control relay
chatter by creating a deadband where no relay action can occur. The
deadband region extends equally above and below the Setpoint. Note that the
SPAN is the region that extends from the Low Limit (LoLt) value to the High
limit (HiLt) value programmed in the 3rd Menu Level.
EroP Error Protection. The desired state to which the Control and Alarm relay
outputs default in the event of controller power loss.
Setting Control output relay Alarm output relay
0OFF OFF
1OFF ON
2ON OFF
3ON ON
Addr Not used; it must be set to ‘0’.
PVoF PV Offset. Permits the user to offset the PV indication from the actual PV. For
example, if the thermocouple used is producing readings 2ohigher than the
actual temperature across the range, the user can eliminate the 2odifference
by programming a "-2" value for this parameter. Overall range of the setting is
-180 to +180. The default value is '0'.

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tyPE Sensor input selection. Select from the list below:
Setting Input type Notes
00 J type thermocouple
01 K type thermocouple
02 T type thermocouple
03 E type thermocouple
04 B type thermocouple
05 R type thermocouple
06 S type thermocouple
07 N type thermocouple
08 RTD Pt100 ohm (DIN)
09 RTD Pt100 ohm (JIS)
10 Linear mode (voltage or
current input)
The controller is offered in one of four input
configurations; Thermocouple, RTD, Voltage or
Current input.
Conversion from one input type to another
requires a hardware modification. Contact Extech
for information.
For thermocouple configured units, the user can
select from the eight (8) thermocouples shown in
the ‘Input Type’ column of this table by simply
changing the ‘tyPE’ setting.
LoLt Low limit (of Span). Refer to SPAN paragraph below.
HiLt High limit (of Span). Refer to SPAN paragraph below.
A Note about SPAN
SPAN is an important 48VTR parameter and is found by subtracting the Low Limit (LoLt)
from the High Limit (HiLt) parameters. The size of the SPAN affects the size of the
Proportional Band (‘Pb’) in the 2nd Menu Level and the size of the deadband for the
hysteresis parameters in the 3rd Menu Level (‘Hyst’ and ‘A1HY’).
In addition, the SPAN dictates the highest and lowest readings possible for SV and PV
displays. Setpoints and PV readings cannot be displayed higher than the high limit or lower
than the low limit. The user programs the SPAN size by setting the low limit (‘LoLt’) and
high limit (‘HiLt’) parameters in the 3rd Menu Level.
Note that low limit and high limit settings are limited to the range of the selected input type.
To check the allowable low and high limit settings, refer to the ranges listed in the
Specifications section of this manual for the input type in question.
Fourth Programming Menu Level
Press and hold the SCROLL and RETURN keys simultaneously for 5 seconds to enter the
4th menu level from the 3rd menu level. To return to normal operation at any time, press
the RETURN key.
LoCA and HiCA
Low and High Input Calibration values. Refer to ‘Calibration’ Section for
details.
tunE Auto Tuning ‘initialization mode’ selection. This parameter allows the user to
select when an Auto Tune session is automatically initiated by the controller.
Set this parameter as desired from the Table in the Auto Tuning section of this
manual.
To activate Auto Tune manually, refer to the Auto Tuning Section of this
manual.

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Calibration
Important Note: Calibration is rarely required. In addition, special equipment is
required in order to perform a calibration. The calibration procedure cannot be aborted
once the calibration parameters are accessed, therefore do not initiate the calibration
process until fully prepared and qualified to do so. It is safe, however, to scroll through
the 4th Menu Level to view the settings. Follow these steps only if prepared to do so.
1. Access the 4th Menu Level as described in the previous section. ‘LoCA’ (Low
Calibration) is the first parameter to appear.
2. Connect a Thermocouple (mV), RTD (resistance), 4-20mA, or 1-5VDC calibrator to
the controller's input terminals (depending on the controller’s input type).
3. Apply the low input signal to the controller which corresponds to the range you are
using, i.e., for 4-20 mA inputs, 4 mA would now be applied to the controller.
4. Use the UP/DOWN arrows to set the display value that will correspond to a 4mA
input. For example, for a 4-20mA input to display –50 to +150, set ‘LoCA’ to –50.
5. Press and hold the RETURN key for at least 5 seconds and the parameter on the
display will change from ‘LoCA’ to ‘HiCA’ (High Calibration). The Low Calibration
value is now written into the controller's non-volatile memory.
6. Apply the high input signal to the controller, which corresponds, to the range you
are using. For example, for a 4-20mA input controller, apply a 20mA signal.
7. Use the UP/DOWN arrows to set the display value that will correspond to a 20mA
input. For example, for a 4-20mA input to display –50 to +150, set ‘HiCA’ to +150.
8. Press and hold the RETURN key for at least 5 seconds; the meter will return to
normal operation. The High Calibration value is now written into the controller's
non-volatile memory.
9. Input a signal midway between the Low and High Calibration signals previously
applied and verify that the display indicates a value midway between the high
display and the low display value. For the example above, apply 12mA (midway
between 4 and 20mA) to display +50 which is the midway point between the high
and low display values.
10. If the controller does not indicate the expected display values, re-calibrate the
instrument. If the display still does not function correctly, contact Extech
Instruments for technical support or return the instrument for repair or replacement.