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1D Electrophoresis—General

It is important to determine whether the problem is with the power supply, the apparatus or the gel. Often, it helps to switch out the power supply or the lid to see if there is a faulty contact. Also, check to see whether the tape from the bottom of the gel cassette has been removed and whether the buffer core is damaged. Additionally, make sure there is sufficient buffer in the electrophoresis tank to cover the wells of the gel.

Here are possible causes and solutions:

  • Buffers are too concentrated or incorrect. Check buffer recipe; dilute or re-make if necessary.
  • Voltage, current or wattage is set at a higher limit. Decrease power conditions to recommended running conditions.

During IEF, it is common for the current to drop below 1 mA. Most power supplies register this as a “No Load” error and automatically shut off, resulting in the stopping of the gel run. This can be bypassed in some power supplies by disabling or turning off the “Load Check” feature.

During NativePAGE™ runs, it is common for the current to drop below 1 mA. Most power supplies register this as a “No Load” error and automatically shut off, resulting in the stopping of the gel run. This can be bypassed in some power supplies by disabling or turning off the “Load Check” feature.

1D Electrophoresis Chamber Systems—XCell SureLock™ Mini-Cell

Here are possible causes and solutions:

  • Buffers are too dilute. Check buffer recipe; remake if necessary.
  • Upper buffer chamber is leaking. Make sure the buffer core is firmly seated, the gaskets are in place and the gel tension lever is locked.
  • Voltage is set too low. Set correct voltage.

We recommend marking the cassette at the bottom of the wells with a marker pen prior to assembling the Upper buffer chamber. Also, we recommend illuminating the bench area with a light source placed directly behind the XCell SureLock™ Mini-Cell unit.

You may purchase the Novex™ Power Supply Adapters, Cat. No. ZA10001 to help you connect your leads to the power supply.

Here are some suggestions:

  • Check the power supply unit.
  • Double check that the tape on the bottom of the gel cassette has been removed.
  • Make sure that the gel(s) are oriented so that the taller sides of the cassette (with the printing) are facing the outside of the electrophoresis unit.
  • Make sure that the inner buffer chamber is filled sufficiently so that the wells are covered with buffer. If the wells are not covered, check for leaks and reseal.
  • Double check to see if there are any loose electrodes or connections on the Mini Cell unit.

1D Electrophoresis Chamber Systems—Mini Gel Tank

Here are possible causes and solutions:

  • Buffers are too dilute. Check buffer recipe; remake if necessary.
  • Buffer chamber is leaking. Make sure the cassette clamp is firmly seated, the gaskets are in place and the cassette clamp is locked.
  • Current is set too low. Set correct current.

Here are possible causes and solutions:

  • Buffers are too concentrated or incorrect. Check buffer recipe; dilute or re-make if necessary.
  • Current is set at a higher limit. Decrease current to recommended running conditions (see Page 8 of the manual).

Here are possible causes and solutions:

  • Tape left on the bottom of the cassette. Remove tape from bottom of cassette.
  • Connection to power supply not complete. Check all connections with a voltmeter for conductance.
  • Insufficient buffer level. Make sure there is sufficient buffer in the electrophoresis tank to cover the wells of the gel.

We recommend marking the cassette at the bottom of the wells with a marker pen prior to placing the cassette in the electrophoresis tank.

1D Electrophoresis Chamber Systems—Bolt™ Mini Gel Tank

Our new Bolt™ Bis-Tris Plus gels have 10 cm gel cassettes and are designed to be used with the Mini Gel Tank (Cat. No. A25977). To run these gels with the Bolt™ Mini Gel Tank, for optimal results, upgrading of the tank is necessary by replacing the black 10.5 cm cassette clamp cam handles with gray 10 cm cassette clamp cam handles (Cat. No. A26732). Instructions for replacement of the cam handles can be found on Page 20 of the manual or in this video.

In the event that you do not have the gray cassette clamp cam handles (Cat. No. A26732), please follow the instructions on Page 22 of the manual for running 10 cm Bolt™ Bis-Tris Plus gels using the Bolt™ Mini Gel Tank.

Here are possible causes and solutions:

  • Buffers are too dilute. Check buffer recipe; remake if necessary.
  • Buffer chamber is leaking. Make sure the cassette clamp is firmly seated, the gaskets are in place and the cassette clamp is locked.
  • Voltage is set too low. Set correct voltage.

We recommend marking the cassette at the bottom of the wells with a marker pen prior to placing the cassette in the gel runner tank.

Here are some causes and remedies for wavy dye fronts:

  • Difference in buffer fill level between the inner and outer buffer chambers. both buffer chambers must be filled up to the electrode with wells completely covered. This will not only prevent leaks from the inside to the outside but will also act a heat sink and prevent wavy dye fronts.
  • Using running buffer that was diluted more than 1X. we recommend using 1X running buffer.
  • Using old running buffer. make sure that the running buffer is fresh and don’t reuse the running buffer.

It is likely that the Bolt™ gel cassette was inserted backwards into the unit (large plate facing the front and the wells facing the back) even though this is pretty difficult to do. When the gel is inserted backwards, the current flows from the bottom of the gel to the top, resulting in the samples running in the opposite direction. Reversing of the leads will switch the direction of the gel run, however, this will cause the current to flow from the anode to the cathode. The cathode electrode is made of stainless steel with platinum coating, and the anode electrode is made of platinum wire. Flow of electrons from the anode to the cathode will result in rusting of the steel core. On the other hand, when the leads are connected properly, the electrons flow from the cathode to the anode and the recipient of the electrons is the platinum wire that does not rust.

Note: When the gel cassette is inserted properly, the lettering (gel type, SKU and expiration date) printed on the cassette will be backwards (reads from right to left).

Here are some likely reasons and remedies:

  • Leaking of buffer from the inside of the tank to the outside. Leaking is most likely due to inappropriate removal of cassettes, which can lead to the gasket not sitting properly and loss of a good seal. We recommend pushing the gasket down with the thumb.

  • Not covering the wells completely with the buffer. We recommend filling the tank up to the electrodes prior to inserting the gel cassettes. Complete filling of the tank not only prevent leaks from the inside to the outside but also acts as a heat sink.

  • Not removing the tape from one of the gel cassettes. Make sure that the tape is removed from both gel cassettes before inserting them into the tank.

  • Not placing the gel cassette all the way to the bottom of the tank prior to clamping it (this will create a bypass of the current at the bottom, so the gel will run slower or not run at all).

1D Electrophoresis Chamber Systems—XCell4 SureLock™ Midi-Cell

Here are possible causes and solutions:

  • Voltage is set too low. Set correct voltage as described in the manual.
  • Buffers are too dilute. Check buffer recipe; re-make if necessary.
  • Upper buffer chamber is leaking. Make sure the buffer core is firmly seated. If you are using the buffer dam, make sure the dam is properly positioned in the core. If the core gasket is damaged, replace with a fresh gasket. Check to ensure that the XCell4 SureLock™ Assembly is in the locked position.

Here are possible causes and solutions:

  • Tape has not been removed from the bottom of the cassette. Remove tape from the bottom of the cassette.
  • Connection to power supply not complete. Check all connections with a voltmeter for conductance.
  • Insufficient buffer level. Make sure the buffer in the Upper Buffer Chamber (cathode) is covering the wells. Be sure there is sufficient buffer (up to the fill line) in the Lower Buffer Chamber.
  • Buffer is leaking from the Upper Buffer Chamber. If the level of running buffer drops, it indicates that the electrophoresis core and cassettes are not properly seated. Repeat the assembly and check to ensure the XCell4 SureLock™ Assembly is in the locked position.

We recommend using Novex™ Power Supply Adapters (Cat. No. ZA10001) to help you connect the leads to your power supply. These adapters are supplied along with the XCell4 SureLock™ Midi-Cell. If these adapters don’t work, you may contact the manufacturer of the power supply to see if other options are available.

1D Electrophoresis Power Supplies—PowerEase™ 300W Power Supply

Here are possible causes and solutions:

Cause Solution
AC power cord is not connected Check AC power cord connections at both ends. Use the correct cord.
The fuse has blown Replace the fuse

Here are possible causes and solutions:

Cause
Solution
Electrophoresis leads are not connected to the power supply or to the electrophoresis unit(s), or there is a broken circuit in the electrophoresis cell Check the connections to the power supply and on your electrophoresis cell to make sure the connection is intact; check condition of wires in electrophoresis unit. Close the circuit by reconnecting the cables. Press Start/Pause to restart the run.
High resistance due to tape left on a pre-cast gel, incorrect buffer concentration, or incorrect buffer volumes in the electrophoresis cell Correct the condition by making sure the tape is removed from the pre-cast gel, buffers are prepared correctly, and the recommended volume of buffer is added to the electrophoresis unit.
Current has dropped below acceptable rating (10 mA) The power supply has a built-in “No Load Detection” feature that can detect when the current drops below the acceptable rating of 10 mA.

This indicates that the circuit has been interrupted. Please check the following:

  • Verify that the running buffer is correct.
  • Verify that all cables are attached correctly.
  • Turn the Power switch off and on again; restart application.
  • If you cannot restart the instrument, turn off the power, disconnect the power cord from the outlet, and contact Technical Service by sending an e-mail to techsupport@lifetech.com.

This is most likely due to a ground leak detected during the run. Check the electrophoresis system for improper grounding and restart the power supply by turning the Power switch off and on.

This is due to overheating of the power supply. Please do the following:

  • Turn off power supply. Check for sufficient airflow around the power supply fan. After cooling down, restart the power supply by turning the Power switch to the on position.
  • If you cannot restart the instrument, turn off the power, disconnect the power cord from the outlet, and contact Technical Service by sending an e-mail to techsupport@lifetech.com.

Here are possible causes and solutions:

Cause Solution
Load exceeds 3 A The output maximum on the power supply is 3 A, so make sure that it is not exceeded.
Blown fuse in the power supply Replace fuse following instructions on Page 19 of the manual.
Incorrect input voltage
Check input voltage switch near power inlet.

Here are likely reasons why this might happen:

  • Electrophoresis systems were added or removed during a run
  • Buffer leaking in a connected system
  • Excessive temperature increase
  • Excessive buffer evaporation
  • Loose connection in a connected system
  • Current set too low

Here are the scenarios for this error with likely causes and solutions:

  • Voltage changes to current
    • Current limit was set too low due to which the ceiling for current was hit and constant mode changed from voltage to current. Increase current limit to 3 A.
  • Current changes to voltage
    • Voltage was set to low due to which the ceiling for voltage was hit and constant mode changed from current to voltage. Increase voltage limit to 250 V.

One extra fuse is supplied with the PowerEase™ 300W Power Supply. For detailed instructions on replacing the fuse, please refer to Page 19 of the manual.

During NativePAGE™ electrophoresis, it is common for the current to drop below 1 mA. The PowerEase™ 300W Power Supply will register this as a “No Load” error and automatically shut off, resulting in the stopping of the gel run. Since there is no way to disable/turn off the “Load Check” feature in the PowerEase™ 300W Power Supply, we do not recommend using it for Native-PAGE electrophoresis.

1D Electrophoresis Power Supplies—PowerEase™ 90W Power Supply

Here are possible causes and solutions:

Cause Solution
AC power cord is not connected Check AC power cord connections at both ends. Use the correct cord.
The fuse has blown Replace the fuse
Cause Solution
Electrophoresis leads are not connected to the power supply or to the electrophoresis unit(s), or there is a broken circuit in the electrophoresis cell Check the connections to the power supply and on your electrophoresis cell to make sure the connection is intact; check condition of wires in electrophoresis unit. Close the circuit by reconnecting the cables. Press Start/Pause to restart the run.
High resistance due to tape left on a pre-cast gel, incorrect buffer concentration, or incorrect buffer volumes in the electrophoresis cell Correct the condition by making sure the tape is removed from the pre-cast gel, buffers are prepared correctly, and the recommended volume of buffer is added to the electrophoresis unit.
Current has dropped below acceptable rating (4 mA) The power supply has a built-in “No Load Detection” feature that can detect when the current drops below the acceptable rating of 4 mA.
  • Verify that the running buffer is correct.
  • Verify that all cables are attached correctly.
  • Turn the Power switch off and on again; restart application.
  • If you cannot restart the instrument, turn off the power, disconnect the power cord from the outlet, and contact Technical Service by sending an e-mail to techsupport@lifetech.com.

This is most likely due to a ground leak detected during the run. Check the electrophoresis system for improper grounding and restart the power supply by turning the Power switch off and on.

This is due to overheating of the power supply. Please do the following:

  • Turn off power supply. Check for sufficient airflow around the power supply fan. After cooling down, restart the power supply by turning the Power switch to the on position.
  • If you cannot restart the instrument, turn off the power, disconnect the power cord from the outlet, and contact Technical Service by sending an e-mail to techsupport@lifetech.com.

Here are possible causes and solutions:

Cause Solution
Load exceeds 500 mA The output maximum on the power supply is 500 mA, so make sure that it is not exceeded.
Blown fuse in the power supply Replace fuse following instructions on Page 17 of the manual
Incorrect input voltage
Check input voltage switch near power inlet.

Here are likely reasons why this might happen:

  • Electrophoresis systems were added or removed during a run
  • Buffer leaking in a connected system
  • Excessive temperature increase
  • Excessive buffer evaporation
  • Loose connection in a connected system
  • Current set too low

Here are the scenarios for this error with likely causes and solutions:

  • Voltage changes to current. Current limit was set too low due to which the ceiling for current was hit and constant mode changed from voltage to current. Increase current limit to 500 mA.
  • Current changes to voltage. Voltage was set to low due to which the ceiling for voltage was hit and constant mode changed from current to voltage. Increase voltage limit to 300 V.

One extra fuse is supplied with the PowerEase™ 90W Power Supply. For detailed instructions on replacing the fuse, please refer to Page 17 of the manual.

1D Electrophoresis Power Supplies—PowerEase™ 500 Power Supply (discontinued as of December 31, 2013)

Here are possible causes and solutions:

  • Power cord not connected or the fuse has blown. Check power cord connections at both ends or replace the fuse
  • Secondary power off. Press the Power button on the keypad.

Note: The PowerEase™ 500 Power Supply has been discontinued as of December 31, 2013 and our alternatives are the PowerEase™ 90W Power Supply and PowerEase™ 300W Power Supply.

Here are possible causes and solutions:

  • Electrophoresis cell(s) are not connected, are disconnected during the run, or there is a broken connection in the electrophoresis cell. Check the connections to the power supply and on your electrophoresis cell to make sure the connection is intact.
  • High resistance due to tape left on a pre-cast gel, incorrect buffer concentration, or incorrect buffer volumes in the electrophoresis cell. Press the Stop button. Correct the condition by making sure the tape is removed from the pre-cast gel, buffers are prepared correctly, and the recommended volume of buffer is added to the electrophoresis cell. Restart the method.

Note: The PowerEase™ 500 Power Supply has been discontinued as of December 31, 2013 and our alternatives are the PowerEase™ 90W Power Supply and PowerEase™ 300W Power Supply.

We recommend resetting the unit by holding front panel Power button down while switching rear power switch off and then on again. Release front Power button.

Note: The PowerEase™ 500 Power Supply has been discontinued as of December 31, 2013 and our alternatives are the PowerEase™ 90W Power Supply and PowerEase™ 300W Power Supply.

This happens when the buffer temperature exceeds the preset temperature limit. We recommend checking the run conditions for the correct current and power settings. Also, make sure the buffer is prepared correctly and raise the temperature limit.

Note: The PowerEase™ 500 Power Supply has been discontinued as of December 31, 2013 and our alternatives are the PowerEase™ 90W Power Supply and PowerEase™ 300W Power Supply.

This indicates that the number of gels selected exceeds the set current limit. Since the number of gels is limited by the maximum current available, we recommend decreasing the number of gels or changing the current settings.

Note: The PowerEase™ 500 Power Supply has been discontinued as of December 31, 2013 and our alternatives are the PowerEase™ 90W Power Supply and PowerEase™ 300W Power Supply.

This indicates that the number of gels selected exceeds the set power limit. Since the number of gels is limited by the maximum power available, we recommend decreasing the number of gels or changing the power settings.

Note: The PowerEase™ 500 Power Supply has been discontinued as of December 31, 2013 and our alternatives are the PowerEase™ 90W Power Supply and PowerEase™ 300W Power Supply.

Here are instructions for replacing the fuse on the PowerEase™ 500 Power Supply:

  1. Turn off the main power switch at the rear of the PowerEase™ 500 Power Supply and detach the power cord from the rear of the PowerEase™ 500 Power Supply.
  2. Open the fuse compartment located inside the Power Entry Module (see page 8 of the manual for rear view of the PowerEase™ 500 Power Supply) by inserting a small flat blade screwdriver into the slot above the On/Off switch. Turn the screwdriver to gently pry open the fuse compartment.
    Note: The fuse compartment will not open with the power cord in place.
  3. Pull the fuse holder out of the compartment and inspect the fuse. If the fuse is burned or if there is a break in the fuse element, replace the fuse with the identical type fuse (see the figure on page 29 of the manual).
  4. Place the fuse holder back into the compartment, making sure that the arrow on the fuse holder points in the same direction as the arrow on the inside of the fuse compartment.
  5. Snap the cover closed.

Note: Extra fuses used to be supplied with the PowerEase™ 500 Power Supply that has been discontinued as of December 31, 2013.

This error message occurs because the power supply detects that the current running through the setup is not sufficient. This error message is most common when the PowerEase™ 500 power supply is used to run an IEF gel or NativePAGE™ Blue gel is run, where the current can drop to very low levels. This problem can be avoided by disabling "Load Check" (do this only if you get the error message); in the menu screen that shows the run parameters, you can go up to the “Load Check” by clicking on the left arrow while the voltage is highlighted. Change from “on” to "off" for "Load Check" by using the using the up or down arrow (see images below). This change should not cause a problem in the running of the gel.

Note: The PowerEase™ 500 Power Supply has been discontinued as of December 31, 2013 and our alternatives are the PowerEase™ 90W Power Supply and PowerEase™ 300W Power Supply.

The PowerEase™ 500 Power Supply has been discontinued as of December 31, 2013. We do not provide schematics, parts, or a repair service for this instrument.

The PowerEase™ 500 Power Supply has been discontinued as of December 31, 2013. We do not offer a recalibration service for this instrument.

The high voltage indicator light (amber or red) is a warning light that indicates that the power source is in operation. Do not unplug the leads when this light is on.

1D Electrophoresis Accessories

Gels turn white when they are dried too rapidly, usually in an environment that is too ventilated, drafty, or warm. You can remedy this problem by dabbing the gel with deionized water on a Kimwipe™ tissue to rehydrate the white areas. Re-dry the gel in a dark, dry, non-drafty place, such as a drawer or cabinet.

Usually it is not necessary to peel off the cellophane. If your signal is very faint and you are concerned about getting an exposure, you can rub the top surface of your gel with a damp towel and then peel off the cellophane. Then air dry the gel for a few minutes and perform autoradiography.

Please see below for possible causes and solutions:

Cause Solution
Air trapped between cellophane layers
Apply adequate Gel-Drying solution to prevent bubbles between the gel and cellophane assembly
Tension on cellophane too strong Take care not to stretch the cellophane during dryer assembly
Rough edges or small cracks on gel edges
Trim rough edges from the gel to eliminate starting points for cracks
Cellophane slips during drying Make sure clamps hold all four edges of the dryer assembly firmly

2D Electrophoresis Chamber Systems—ZOOM™ IEF Fractionator System

Here are possible causes and solutions:

  • Low current shut-off feature enabled. Check the power supply. Be sure to override the low current shut-off feature as recommended by the manufacturer to enable the power supply to operate at low current.
  • Air-bubble in chambers. Avoid trapping any bubbles in the Chamber Assembly Tube or in Sample Chambers. If there are any bubbles, use a gel loading tip to break the bubbles.

Here are the possible causes and solutions:

  • Incorrect buffers used in the buffer reservoirs. Use diluted anode and cathode buffers as described in the manual. If you are preparing your own anode and cathode buffers (see manual for a recipe), use lysine (free base) and arginine (free base). Do not use lysine HCl and arginine HCl.
  • Poor quality reagents used or urea is degraded. Use high-quality, proteomic-grade reagents for sample and buffer preparation. Use freshly prepared urea solutions or stored frozen at –80 degrees C. De-ionize urea solutions on a mixed bed ion exchanger resin using manufacturer’s recommendations.

Here are the possible causes and solutions:

  • Incorrect buffers used in the buffer reservoirs. Use diluted anode and cathode buffers as described in the manual. We recommend using a power supply capable of setting power and current limit to avoid accidental damage to the fractionator due to high currents.
  • High salt concentration. Limit the salt concentration in the samples to 10 mM or less.

A black friction O-ring is attached to the Anode End Sealer. If the Anode End Sealer is difficult to insert into the Chamber Assembly Tube, remove the black friction O-ring.

Removal of the friction O-ring may result in sliding of the Anode End sealer and Sample Chambers into the Chamber Assembly Tube. If this results, add the friction O-ring on the Anode End Sealer.

Inspect the Sample Chamber to check any damage to the Sample Chamber or groove. Use another Sample Chamber included in the Spares Box.

Try lubricating the Cathode Chamber Seal (black O-ring) with silicone by lightly dabbing silicone around the seal with a swab. Silicone is typically available in most laboratories. If the Chamber Seal is damaged, replace with a new Chamber Seal included in the Spares Box.

This could potentially be due to leakage between Sample Chambers. Assemble the Sample Chambers in the Chamber Assembly Tube as described in the manual. Improper assembly of the fractionator will not produce proper sealing and result in leaking and contamination of fractions. Be sure to properly insert the Sample Chamber O-ring Seals on the groove of the Sample Chamber and place the ZOOM™ Disks on the chamber as shown in the manual.

2D Electrophoresis Chamber Systems—ZOOM™ IPGRunner™ System

A possible reason is poor contact between electrodes or incomplete circuit. Make sure that you have added 600 μL deionized water to the Electrode Wicks and the gel is exposed at the anodic and cathodic ends of the cassette. Check the power supply. Be sure to set the ‘Load Check’ to off to enable the power supply to operate at low current.

Here are the possible causes and solutions:

  • Low protein load. Increase the protein load. Use an accurate and sensitive protein estimation method.
  • Improper sample preparation. Increase solubilization reagents. Use at least 8 M urea for solubilization. Add DTT and non-ionic detergents (see manual for details)
  • Strip not correctly oriented. Align the strip correctly as described in the manual. Be sure to have the gel side up when loading the strip into the ZOOM™ IPGRunner™ Cassette.
  • Air bubbles between the strip and 2D gel. Smooth out any air bubbles.
  • Insensitive detection method. Use sensitive detection methods such as silver staining or immunoblotting.

Here are the possible causes and solutions:

  • High salt concentration. Limit the salt concentration in the samples to 10 mM or less. If possible, adjust the salt concentration of your sample by ultrafiltration, dialysis, or gel filtration.
  • High Power. Check power settings.
  • Poor strip rehydration. Rehydrate the strips in 140 μL sample rehydration buffer for 1 hour as described in the manual. Rehydration can be extended to overnight if you use 155 μL rehydrating buffer. Make sure that the rehydration buffer is covering the strip completely.
  • Liquid in the inner chamber. Do not pour any liquid or buffer in the inner chamber. Check for any leakage in the inner chamber.

2D Electrophoresis Power Supply—ZOOM™ Dual Power Supply

Here are possible causes and solutions:

  • AC power cord is not connected. Check AC power cord connections at both ends. Use the correct cords.
  • The fuse has blown. Replace the fuse as described in the manual.

Here are possible causes and solutions:

  • High voltage application is set to run on a very low current. DISABLE No Load alarm on the Running Screen (see manual for details), for example when performing an isoelectric focusing application.
  • Electrophoresis leads are not connected to the power supply or to the electrophoresis unit(s), or there is a broken circuit in the electrophoresis cell. Check the connections to the power supply and on your electrophoresis cell to make sure the connection is intact; check condition of wires in electrophoresis unit. Close the circuit by reconnecting the cables. Press Stop/Start to restart the run.
  • High resistance due to tape left on a pre-cast gel, incorrect buffer concentration, or incorrect buffer volumes in the electrophoresis cell. Correct the condition by making sure the tape is removed from the pre-cast gel, buffers are prepared correctly, and the recommended volume of buffer is sadded to the electrophoresis unit.

This indicates that the circuit is interrupted. Please check the following:

  • Verify that the running buffer is correct.
  • Verify that all cables are attached correctly
  • Turn the Power switch off and on again; restart the application.
  • If you cannot restart the instrument, turn off the power, disconnect the power cord from the outlet and contact Technical Support at techsupport@lifetech.com.

This indicates that a ground leak was detected during the run. Check the electrophoresis system for improper grounding. Restart the power supply by turning the Power switch off and on.

This indicates that the power supply is overheating. Turn off the power supply and check for sufficient airflow around the power supply fan. After cooling down, restart the power supply by turning the Power switch to the on position. If you cannot restart the instrument, turn off the power, disconnect the power cord from the outlet, and contact Technical Support at techsupport@lifetech.com.

Here are instructions for replacing the fuse on the ZOOM™ Dual Power Supply:

Note: One extra fuse is supplied with the ZOOM™ Dual Power Supply.

  1. Turn off the main power switch at the rear of the ZOOM™ Dual Power Supply and detach the power cord from the rear of the ZOOM™ Dual Power Supply.
  2. Open the fuse compartment located inside the Power Entry Module (see page xiii of the manual for rear view of the ZOOM™ Dual Power Supply) by inserting a small flat blade screwdriver into the slot above the On/Off switch. Turn the screwdriver to gently pry open the fuse compartment.
    Note: The fuse compartment will not open with the power cord in place.
  3. Pull the fuse holder out of the compartment and inspect the fuse. If the fuse is burned or if there is a break in the fuse element, replace the fuse with the identical type fuse (4 A/250 V) provided in the fuse holder (see figure on page 39 of the manual).
  4. Place the fuse holder back into the compartment.
  5. Snap the cover closed.