KEY HT-300 User manual

INSTRUCTIONS
for
MODEL NO. HT-300/500
HARDNESS TESTER
VERSION 1.0
KEY INTERNATIONAL, INC.
480 ROUTE 9
ENGLISHTOWN, NJ 07726
Phone: [phone] Fax: [phone]

Key International, Inc. •Englishtown, NJ •U.S.A. Page 2
Table of Contents
General Description.....................................................................................................................................4
Introduction ..............................................................................................................................................4
Specifications ...........................................................................................................................................4
Method of Operation ................................................................................................................................5
Putting into Operation..................................................................................................................................5
Wiring.......................................................................................................................................................5
Inserting the Chart Paper..........................................................................................................................6
Operating Keyboard.....................................................................................................................................7
Operating controls....................................................................................................................................7
Power Button.........................................................................................................................................7
Restart Switch .......................................................................................................................................7
Stop Button............................................................................................................................................7
Start Button ...........................................................................................................................................7
Printer....................................................................................................................................................7
Adjustments .................................................................................................................................................8
Limit Switch.............................................................................................................................................8
Unit...........................................................................................................................................................8
Switch for units .....................................................................................................................................8
Adjustment................................................................................................................................................8
Starting the test program.......................................................................................................................8
Zero balance..........................................................................................................................................8
Calibration.............................................................................................................................................9
Explanation of error information..............................................................................................................9
CONNECTION POSSIBILITIES .............................................................................................................10

Hardness Tester •Model HT-300/500 •Version 1.0 Page 3
Connection of an external start-keY.......................................................................................................10
Connection to arallel-interface (94-00442) (OPTION).......................................................................10
Plug connections.....................................................................................................................................10
a) 5-pin socket:....................................................................................................................................10
Spare Parts List.......................................................................................................................................16

Key International, Inc. •Englishtown, NJ •U.S.A. Page 4
General Description
Introduction
The PTB 300 is a high performance hardness tester, which can accurately measure the tensile strength of
tablets, ampoules, food and other articles, either in single or in series operation. The tensile strength can
be printed out in Kilopond (Kp), Newton (N) or Strong Cobb (SC) units, according to the operator's
specifications.
Specifications
Sample Diameter 4 - 40 mm
Jaw Stroke 4 - 40 mm (externally adjustable)
Chart Speed 3 mm/second
Force Increase 2 Kp/second
Measuring Range HT-300: 0.5 - 30 Kp
HT-500: 0.8 - 50 Kp
, (convertable to Newtons (N), Kilo Ponds (Kp), or Strong
Cobbs (Sc) )
Measured Value Printed on the built in printer
Resolution 0.1 Kp
Accuracy +/- 1% Full Scale
Measuring Jaws Interchangable for different sample forms (tablets,
ampoules, etc...)
Dimensions (W) 530 mm x (D) 240 mm x (H) 180 mm
Power Supply Switch Selectable, 110/220 volt, 50/60 Hz., Single Phase
Input External Start Switch (optional)
Output RS-232 or BCD Parallel

Hardness Tester •Model HT-300/500 •Version 1.0 Page 5
Method of Operation
Figure 1: Method of Operation
After pressing the START-key, the zero-value of the load cell is teterminet ant aeoret in the
microprocessor. If the value is within the permittet range, the motor, controllet by the regulator-unit ant
the motor-amplifier, causes the plunger to move at a constant speed towarta the apecimen. As aeon aa
the plunger touches the specimen and protuces a force on the loat cell, the microprocessor switches the
regulator on 80 that a lineirly increasing force is producet via the control circuit (loaf
cell-regulator-motor-specimen) until the specimen breaks. The decreasing signal from the loat cell
indicates to the microprocessor, which subtracts from this value the zero-value (automatic zeropoint
correction) and prints out the calculated value in the desired units (N, kp, SC).
The spring-unit in front of the loat cell provites a smooth transition from the constant velocity phase of
the plunger to the linear power increase phase.
Putting into Operation
NOTE: Before putting the HT-300 into operation, check the voltage setting switch
on the back of the unit (220 V resp. 115 V) and make sure that the operating voltage
corresponds to the local power supply.
Wiring
•connect the signal cables to any additonal units
•connect the signal cable from the external start-key (if fitted)

Key International, Inc. •Englishtown, NJ •U.S.A. Page 6
•connect power supply line.
Figure 2: Back of Unit
1. Output 25-pin, plug female type D (parallel-interface)
2. Power input with fuse (250 mA at 220 Volt, 500 mA at 115 Volt)
3. Voltage selector switch 220 V / 115 V
4. Waste Container: Under the container is the switch for units selection, the potentiometer for zero
adjustment and the potentiometer for balancing the load cell
5. Under the Waste container and behind the access door is the switch for units selection, the
potentiometer for zero adjustment and the potentiometer for balancing the load cell
6. Motor fuse 400 mA
7. Input socket plug (optional external start switch)
Inserting the Chart Paper
The instrument should never be operated without paper.
To insert the paper open the cover (1). Slide in a roll of paper (2), with the dim side up, onto the spindle
(3).
Then feed the paper into the printer (4) and while turning the paper transport wheel (5) lead the paper
through the printer.

Hardness Tester •Model HT-300/500 •Version 1.0 Page 7
Operating Keyboard
Operating controls
Power Button
Switch on the instrument by pressing the POWER button (1). When pressed the switch should iluminate
to indicate that the power has been switched on.
Restart Switch
Using the thumb wheel selector switch (4) the operator can set the machine to automatically start a
series of tests. When set to position 0 the automatice testing option is turned off. Selecting positions
from 1 to 9 will activate the automatic operation mode. In the automatic mode the operator places a
sample for testing between the jaws and presses the start button. After the test is completed the jaws
will move away and automaticaly start the next test after the number of seconds as set by the restart
switch. If any errors occur, see errors section in this manual, the automatic operation will stop and can
be restarted by pressing the start button. After all the samples have been tested press the stop button or
set the restart switch to 0 and the automatic operation will be stopped.
Stop Button
By pressing the STOP button the testing procedure can be interruptet at any time.
Start Button
a) By pressing the start button (6) the single measuring procedure can be started (RESTART switch (4)
must be set to O). The START button is only operative when the movable plunger is in neutral position.
b) With the START button a series of measurements can be started (RESTART switch (4) must not be
set to O).
Printer
When a printout is terminated and the printing paper has stopped moving, or when the paper is torn,
move the release-lever (2) in direction of the arrow and remove the paper from the printer. The release
lever must not be touched during operation.

Key International, Inc. •Englishtown, NJ •U.S.A. Page 8
The printer (3) should never be operated without paper, otherwiae a clean printout can not be
guaranteed.
Adjustments
Limit Switch
By means of the limit switch the jaw stroke can be adjusted from approximately 4 - 40 mm.
Unit
Using this switch following units can be selected as required: Kp, N, SC.
Switch for units
Units Selection Switch
Potentiometer "GAIN"
Potentiometer "ZERO"
Adjustment
A test program is incorporated in the PTB 300 which allows to check and if necessary to adjuat the
zero-point- and amplification adjustment without the neet of special measuring equipment.
Starting the test program
The movable plunger must be in neutral position. If you are calibrating the unit it is best to turn the
stroke adjustment knob so the jaws are open the widest.
Set restart switch to 0.
Press STOP key and hold down while START key is pressed.
Release both keys at the aame time.
The message "HT 300 xx.xx" is printed out. (The number xx.xx is important for service, requests etc.).
Zero balance
After starting the test program set the RESTART switch to 1. Presa STOP key.
The message "yyyy" is printed out. V

Hardness Tester •Model HT-300/500 •Version 1.0 Page 9
The value "yyyy" must lie between 20 and 60. Is this not the case, adjust the potentiometer "ZERO" so
that the value does reach this range. By pressing the STOP-key the zero point can be printed out as often
as required. Differencea of less than 7 between the single printouts are normal and do not influence the
accuracy of the instrument.
Calibration
a) Turn instrument to the side b) Set RESTART-switch on position 2 c) Press STOP-key d) Set
RESTART-switch on position 3 e) Place calibration weight
f) Press STOP-key
The message "zzzz N" is printed out (printout always in N, re
gardless of the setting of the units-switch)
g) Remove calibration weight
h) If necessary adjust potentiometer "GAIN"
1) Repeat operations b) to h) until the balance is satisfactory.
Explanation of error information
NO SAMPLE: No specimen has been insertet.
STOP:
> MAX: T.~.e specimen withstood 300 N.
ZERO:- when pressing the START-key:
The specimen ia already pressing on the loat cell,
or: zero point adjustment is incorrect (see test prog
gram: zero point adjustment)
- during pre-run:
When pressing the START-key the specimen has
pressed stronger on the load cell than during the
pre-run.
The STOP-key interrupts the run of the program.

Key International, Inc. •Englishtown, NJ •U.S.A. Page 10
CONNECTION POSSIBILITIES
Connection of an external start-keY
It ia possible to connect an external atart-key (e.g. footswitch) to the 5-pin aecket; the function of an
external atart-key ia identical to that of the internal one.
When starting, the sockets 1 ant 3 muat be short-circuited (30 Y, 30 mA).
Socket 5 i8 earthed when the movable plunger is in ita neutral position. (Open-collector-output NPN,
allowable load 30 V, 50 mA).
Connection to arallel-interface (94-00442) (OPTION)
. . P
Data from the PTB300 are only given out, if the lead FO i8 held on OV.
- If the lead ]7S ia held on OV, the PTB300 keeps the data output until the lead 13[ alao indicates OV.
- The data are valid when the "LOAD"-impulse haa atarted and remain unchanged until the break of the
next specimen haa occured.
Plug connections
a) 5-pin socket:
Pin 1: START-signal (input)
2: no connection
3: earth
4: no connection
5: neutral position of plunger (output)