QBT series Block Heaters Operating Instructions Issue 7 Aug 2004

QBT Block Heaters QBT1 holds 1 block QBT2 holds 2 blocks QBT4 holds 4 blocks Covers QLS for QBT1, QBT2 QLL for QBT4

QBT Block Heater

CONTENTS 1

Safety

5

2

Installation

6

2.1

Unpacking

6

2.2

Assembly

6

3

Operation

7

3.1

Controls and indicator lamps

7

3.2

Setting the temperature

7

3.3

Setting the overtemperature cut-out

7

3.4

Resetting the overtemperature cut-out

7

3.5

Measuring temperature

8

4

Accessories

8

4.1

Individual blocks for test tubes, universal bottles, microcentrifuge tubes.

8

4.2

Safety Covers

8

5

Fault diagnosis

9

6

Technical specification

10

7

Maintenance and service

10

7.1

Cleaning

10

7.2

Replacement of fuses

10

8

Guarantee

11

9

Service

11

Part No. 14631-Issue 7

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QBT Block Heater

View on underside Fuse drawer catch Push in the direction of the arrow to release

Fuse drawer

IEC power socket

Figure 1

Figure 2

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QBT Block Heater

1

Safety

The following symbols marked on the equipment mean:Caution: Read these operating instructions fully before use and pay particular attention to sections containing this symbol Caution: Surfaces can become hot during use. Always observe the following safety precautions • • • • • • • • • • • • • • • • • • •

Use only as specified by the operating instructions, or the intrinsic protection may be impaired. After transport or storage in humid conditions, dry out the unit before connecting it to the supply voltage. During drying out the intrinsic protection may be impaired. Connect only to a power supply with a voltage corresponding to that on the serial number label. Connect only to a power supply which provides a safety earth (ground) terminal. Before moving, disconnect at the power supply socket. Do not remove the IEC connector. Do not check the temperature by touch, use the temperature display or a thermometer. To reduce the risk of eye injury during high temperature operation, use safety goggles or spectacles. Do not touch surfaces which become hot during high temperature operation. If the alarm lamp is illuminated do not touch the block it may be very hot. Ensure that the operating temperature is less than the maximum operating temperature of your sample material. Set the adjustable overtemperature cut-out after setting or changing the set temperature, and reset it at monthly intervals to check that the cut-out is operating correctly. Ensure that the mains switch is easily accessible during use. Do not block or restrict ventilation slots. If liquid is spilt inside the unit, disconnect it from the power supply and have it checked by a competent person. It is the user’s responsibility to carry out appropriate decontamination if hazardous material is spilt on or inside the equipment. Do not touch the blocks within the unit itself, or after removal, they may be hot. Always remove blocks with the extraction tool supplied. Do not place hot blocks on a flammable surface. Allow the unit to cool down before moving it.

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QBT Block Heater

2

Installation

2.1

Unpacking Remove the packing materials carefully, and retain for future shipment or storage of the unit. The pack should contain: block heater mains cable block extraction tool operating instructions Blocks are supplied separately in their own pack.

2.2

Assembly Fit the mains cable into the IEC power socket on the underside of the unit (see Figure 1). The cable should run towards the back of the unit. Before inserting the blocks check that the heated plate is clean and the bottom of the block is wiped to remove any particles which may affect transfer of heat. Insert the blocks, using the extraction tool provided (see Figure 2). Take care not to drop the blocks; if they are damaged, heat transfer may be affected. Use the maximum number of blocks available (i.e. 4 blocks in a QBT4; 2 blocks in a QBT2; 1 block in QBT1). Place the block extraction tool in the locator hole for future use (see Figure 2). Before switching on for the first time, turn the black set overtemperature knob fully clockwise and press it. Switch on power to the unit.

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QBT Block Heater

3

Operation

3.1

Controls and indicator lamps

Power

Blue knob

Grey button

Black knob

Figure 3 Power (mains) switch. The temperature display normally shows the block temperature in °C. When the grey display set temperature °C button is pressed the set temperature is shown. The set temperature °C (blue knob) sets the required operating temperature. The display set temperature °C (grey button) shows set temperature when pressed. The heater lamp (orange) indicates when the heater is on. The heater lamp is on continuously while the blocks are heating up. As the required temperature is approached, it starts to flash. When the unit is controlling at set temperature, the heater lamp flashes intermittently. The alarm lamp (red) illuminates when the overtemperature cut-out has operated. Set overtemperature push to reset (black knob) sets the overtemperature cut-out. The cut-out operates if the block temperature rises above this temperature. When it has operated, the red alarm lamp illuminates and the heater is switched off. The block temperature continues to be displayed to warn of possible high temperatures.

3.2

Setting the temperature The display normally shows the block temperature. To show the set temperature at any time, press the grey display set °C button. To set the required operating temperature, push the grey display set °C button, whilst turning the blue set temperature °C knob until the required temperature is indicated on the display.

3.3

Setting the overtemperature cut-out To protect both the unit and your samples, the overtemperature cut-out should be set each time the required operating temperature is changed. Using a screwdriver turn the black set overtemperature knob fully clockwise and press to reset. The cut-out is now set at its maximum. Allow the block heater to stabilise at the required operating temperature. Turn the black control slowly anticlockwise using a screwdriver until the red alarm lamp comes on. Press the control and gently turn clockwise until the alarm lamp goes out. Turn the control anticlockwise three quarters of the way back towards the point where the alarm lamp came on. The overtemperature cut-out is now set approximately 10°C above the required operating temperature. Note If the required operating temperature is above 140°C turn the black knob fully clockwise.

3.4

Resetting the overtemperature cut-out If the overtemperature cut-out has operated, the block heater needs to cool to just below the set temperature before the cut-out can be reset.

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QBT Block Heater

3.5

Measuring temperature The block temperature may be checked by placing a temperature probe (maximum diameter 3.5mm) fully into the block extraction hole. An accurate calibrated digital thermometer should be used. It is not recommended to make measurements directly in the test tube. The probe size can cause errors.

4.

Accessories

4.1

Individual blocks for test tubes, universal bottles, microcentrifuge tubes. QB-0 plain block QB-10 for 10mm test tubes QB-12 for 12mm test tubes QB-16 for 16mm test tubes QB-18 for 18mm test tubes QB-24 for 24mm test tubes, universal bottles QB-E0 for 0.5 ml microcentrifuge tubes QB-E1 for 1.5 ml microcentrifuge tubes Any of the above blocks can be used with each of the block heater. The QBT2 and QBT4 can be used with any combination of these blocks. When dissimilar blocks are used the uniformity specification across blocks at 37°C typically rises to ±0.4°C.

4.2

Safety Covers QLS for QBT1, QBT2 QLL for QBT4 The cover restricts the use of test tubes to those less than 125mm in length. Tough, clear polycarbonate covers maintain visibility while preventing anyone from accidentally touching a hot block. They also protect against hot liquids or expensive accidents and are particularly recommended for use during high temperature operation. The cover pack should contain: cover two M3 screws 12mm long two shakeproof washers four plain washers two spacers

Cover Spacer Plain washer Shakeproof washer M3 x 12.0 screw

Plain washer

Figure 4

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QBT Block Heater

5

Fault diagnosis Symptom

Possible cause

Action required

Unit does not operate

Unit not switched on

Switch on

Unit not plugged into power supply

Plug in, switch on

Power supply failure

Check that other electrical appliances on the same circuit are working

Fuse blown in unit or in plug (UK units only)

Check and replace - see 7.1

Alarm lamp on

Overtemperature cut-out has operated

Reset cut-out and check its setting as described in 3.3 and 3.4. If the cut-out operates again or cannot be reset, have the unit checked by a competent person.

Temperature does not rise when expected

Set temperature is lower than block temperature

Check set temperature

Set temperature is too close to ambient

Raise set temperature

Temperature control circuit fault

Have unit checked by competent person

Set temperature is higher than block temperature

Check setting

Temperature control circuit fault

Have unit checked by competent person

Temperature continues to rise when not expected

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6

Technical specification Temperature range Setting range Stability at 37°C Temperature display resolution Supply voltage range Power Rating

Ambient +5°C to 150°C 15°C to 150°C ± 0.1°C 1°C 220-240V or 110-120V: 50/60Hz QBT1 - 150W QBT2 - 300W QBT4 - 600W Overtemperature protection Adjustable, re-settable safety cut-out Uniformity: QBT1 QBT2 QBT4 Within the block at 37°C (°C): ± 0.1 ± 0.1 ± 0.1 Across similar blocks at 37°C (°C): ± 0.2 ± 0.2 ± 0.2 Heat-up rate (ambient to max)(minutes) 40 40 40 Dimensions l/w/h (mm) 180/205/122 230/205/122 330/205/122 This equipment is for indoor use and will meet its performance figures within the ambient temperature range 10°C to 35°C, with maximum relative humidity of 80%. Installation category II (Transient voltages). Pollution degree 2 in accordance with IEC664. For operation at altitudes up to 2000 metres.

7

Maintenance and service All Grant laboratory products are designed to comply with IEC1010-1 and can be flash tested. Some are fitted with radio frequency interference suppressors. Therefore it is recommended that only a d.c. test is performed. The overtemperature cut-out should be checked periodically by turning the black set overtemperature knob anticlockwise until the alarm lamp comes on. The cut-out should then be reset and set-up (see 3.4 and 3.3). If the alarm lamp fails to light with the knob turned fully anticlockwise the block heater should be checked by a competent person. No other routine maintenance is required.

7.1

Cleaning The cases can be cleaned with a damp cloth after disconnection. Do not use solvents. Before using any decontamination or cleaning method except that recommended, check with our Service Department, or in other countries with our distributor, that the proposed method will not damage the equipment.

7.2

Replacement of fuses Remove the blocks Disconnect the unit from the power supply. Remove the IEC plug from the socket in the base. Press down the fuse drawer catch (see Figure 1). Pull out the fuse drawer, check and replace with the correct fuses if necessary. The fuses should be 1.25 x 0.25 inch ceramic quick acting, rated: 220-240V:

QBT1 - 1AF QBT2 - 2AF QBT4 - 5AF

110-120V:

QBT1: 3AF QBT2 - 5AF QBT4 - 10AF

Push back the drawer, and replace the IEC plug.

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QBT Block Heater

8

Guarantee When used in laboratory conditions and according to these operating instructions, this block heater is guaranteed for THREE YEARS against faulty materials or workmanship.

9

Service For service, return for repair to our Service Department or, in other countries, to our distributor. DO NOT RETURN BLOCKS. Service Address: Grant Instruments (Cambridge) Ltd Service Department Shepreth Cambridgeshire SG8 6GB England. Tel: Fax:

Part No. 14631-Issue 7

+44 (0) 1763 260 811 +44 (0) 1763 262 410

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Grant Instruments (Cambridge) Ltd Shepreth Cambridgeshire SG8 6GB England Tel: +44 (0) 1763 260811 Fax: +44 (0) 1763 262410 Email: [email protected] www.grant.co.uk