Home Troubleshooting | new single board

Troubleshooting | new single board

The Brewer software and firmware have a number of diagnostic tests that can be run to check the health of the Brewer and to identify and help resolve problems. Please refer to the Brewer operating manual for further information during the tests and checks described below.

Note: Kipp & Zonen specialists can carry out a lot of troubleshooting remotely via the computer operating the Brewer. The computer must have an internet connection and remote access via a programme such as ‘Teamviewer’ or ‘Logmein’.

These troubleshooting instructions only apply to ‘single-board’ Brewers of the most common configuration. MkII, III or IV with the ‘single-board’ main electronics that has most of the integrated circuits installed in dual-in-line sockets. The most recent MkIII Brewers have a main electronics board with surface mount devices (SMD). The layout is similar, but not identical. First-generation ‘multi-board’ Brewers are completely different. Please contact Kipp & Zonen for support.

Latest single board of the Brewer Spectrophotometer

Resetting the Brewer

Start the Brewer Software. The Brewer should launch communication. After establishing communication you can see status – “Reply” in the left corner of the Brewer software window.

If this message is received then communication has been established between the Brewer and the control computer.

If the instrument does not reply, or does not reset (as seen by motors initializing) when instructed by the computer software, or when power is switched on, the problem is probably within the Brewer. However, it may also be in the power or communication cables, the computer or the software.

The operating software can be re-loaded onto the computer from the original disc to eliminate it as a potential problem. Ensure that the Brewer configuration files are saved as they contain important operating information such as the COM port number and other variables.  Check the configuration files to ensure that none of the files have been corrupted.

Checking the power supply

In order for the Brewer to operate it must receive AC power to its main AC-DC power supply. The AC power cable is connected to the azimuth tracker and then from the tracker to the spectrophotometer by an external cable. There are three points to be checked: the power on-off switch, the green LED indicator on the Brewer and the fuses for the power supply.

Check power LED and cable

If the green LED on the Brewer is illuminated, then there is power to the instrument, and the main power supply is producing +5 VDC. If the LED is not illuminated, it may be that the LED is faulty. Switch off the power, remove the Brewer cover and check if the main power supply cover feels warmer than the ambient temperature. If this cover feels slightly warmer, the LED is faulty. If not, AC power is not reaching the power supply.

In this case, the AC power source should be checked at the AC outlet and the end-to-end continuity of the power cable tested. The AC power should then be connected directly to the Brewer, bypassing the azimuth tracker.

Check power switch and fuses

If the main power supply cover is still not warm, then perhaps the power switch is defective, or a fuse requires replacement. With power disconnected, use an Ohmmeter to confirm that the switch is functional, and check the two fuses (Picture (Figure) 1) next to the power supply cover, as indicated in the picture below. If a fuse needs replacement, ensure that AC power is disconnected, and replace the fuse with a spare of the correct type.


Fuse box of the Brewer new single board

Picture 1 Fuses box

To check the fuse inside the power supply, disconnect AC power from the Brewer, remove the four main power supply cover screws, and check the fuse. Replace it if necessary. Please refer to Picture 2.

Brewer single board, Fuse in the main power supply

Picture 2 Fuse in the main power supply

When re-installing the cover, ensure that all the power supply connectors are firmly engaged and secured. If the switch and fuses are in good order there may be a fault in the power supply.

Check main power supply output voltages

The main power supply DC output voltages can be checked at the test points on J23 of the main electronics board. Please refer to Picture 3.

Fuse in the main power supply

Picture 2 Fuse in the main power supply

Refer to the table below for the correct voltages. Number 10 is the top pin.

Connector X23 pins 1 2 3 4 5 6 7 8 9 10
DC Voltage +5 +5 -5v +12v +12v -12v +24v +2.5v +4.5v GND


Communication checks

If it has been established that there is power at the Brewer, and the motors reset when power is switched on, but that there is no communication between the computer and the Brewer, follow the next steps.


A software reset should be attempted after the “Brewer Failed to Respond” message appears on the computer monitor or if the computer has tried a number of times to establish contact with the Brewer and failed. The software reset is done by typing “ex” and pressing <Enter> key on the computer, or by (re)launching the Brewer software from the DOS prompt. If this fails to establish communications, the serial port may be latched and the computer should be given a powercycle.

Test serial port

Confirm that the computer serial port is operating correctly by running a serial communications program such as RealTerm, Hyperterminal or PuTTy. Please note that HyperTerminal is included in Windows™ XP, but not in Windows™ 7. Make sure the serial port is set to 1200 baud, to full-duplex mode, and that the correct serial port has been selected. Refer to the communications program documentation for correct operation.

Remove the RS-422 to RS-232 converter from the computer serial port and connect pins 2 and 3 of the computer serial port together. While running the communication program in full-duplex mode, characters typed should be seen echoing to the monitor. Disconnecting the jumper wire should stop the echo-back. This test confirms that the computer serial port is operating correctly.

If the computer did not echo the characters, change the Brewer software configuration to use another port or have the defective serial port repaired before doing any further tests.

Check microprocessor mode

If there is still no operation, there may be a firmware problem, or a problem on the main electronics board, so the functionality of this board should be tested.

There is a Red status LED located in the centre of the main board.

Brewer single board LED light status

Picture 4 LED light status

The red LED should be flashing slowly in ‘Cosmac mode’ in ¼ second pulses, as per the following table. If the Brewer is in another mode, change back to the Cosmac mode.

LED mode pulse ¼ sec ¼ sec ¼ sec ¼ sec ¼ sec ¼ sec ¼ sec ¼ sec
Cosmac mode, normal operation On Off Off Off On On On Off
Cosmac mode, with configuration missing On Off Off Off On Off On Off
Loadmode, waiting for code to be downloaded On Off On Off On Off On Off
Loadmode, with bad flash memory On On On On Off Off Off Off
Loadmode, with good flash memory On On On On On On On Off
Opmode, with configuration present On On Off Off On On Off Off
Opmode, without configuration present On On Off Off On Off On Off
Checking, flash memory On Off On Off Off Off Off Off
Changing from loadmode to cosmac or opmode On On On On On On On On

If the LED is not flashing, then the correct main power supply voltages should be confirmed.

Test Main Power Supply

Check the voltages at the main electronics board connector J23, as per section ‘Check main power supply output voltages’. If the power supply values have changed, the power connections should be checked. If they appear normal, and the voltages are still not at proper levels, replacement of the main power supply should be considered.

However, there could be a partial short-circuit in one of the assemblies causing the power supply to be loaded.  Shut the power off and disconnect the power plugs J1 from the main electronics board and J4 from the lamp control board.  Repeat the voltage measurements at the terminal screws on the main power supply and see if all the voltages are present.


Brewer Main board voltages connection point

Picture 5 Main board voltages connection point

If the voltages are correct, then determine which assembly is at fault by installing the connectors one at a time and checking which causes the voltage to drop.

Replace the main power supply if necessary, and ensure when first turned on that the assemblies are disconnected to allow set-up of voltages to the correct values.  The main +5 VDC output is monitored at the main electronics board and should be set to 5.0 VDC, ± 0.1 VDC, with the potentiometer on the main power supply unit.

Restore a Brewer to Cosmac mode

If the red flashing LED on the main electronics board indicates that it is not in the Cosmac mode, and the software has not been successful in correcting it during the reset sequence, then the following procedure should be followed:

Exit the serial communications program and change to the subdirectory c:\bdata\nnn, where nnn – it is a Brewer number.

Change the “brewcmd.ini” to the corresponding com-port and open “brewcmdw.exe”. Observe if the instrument has responded and note which mode is indicated. The program should display the same mode as indicated by the red status LED.

Type ‘readlog <Enter>’ to display the past error history, each line displayed will be a possible clue to the problem that caused the failure. If motor failures have occurred, the status will tell you which motor, and what the failure was. Usually, it is a sensor problem, or a wiring problem, that prevents the motor from resetting. If no problems are displayed, then the system can be placed back into cosmac mode for further testing.

Type ‘loadmode <Enter>’ and following the return of the confirmation ‘loadmode’ and the prompt, type ‘cosmacmode <Enter>’. The motors will reset and within a minute the system will display the status that it is in cosmac mode.

Quit the Brewcmdw program by typing ‘quit <Enter>’.

Run the Brewer software

Run the Brewer operating program by opening “brewer.bat”. Check the correct operation of the instrument. Select routines that you are familiar with and ensure that all the functions and data appear normal.

Brewer support

For help with Brewer problems and questions, for all models, please contact the Kipp & Zonen Brewer team by e-mail to Brewer@kippzonen.com.

For spare parts you can also contact Services@kippzonen.com.

Note: Please always include the Brewer type and serial number, your organisation name, and your contact information with enquiries.