HS3 Service Bulletins & Tips

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HS3 Service Bulletins

HS3-99SB1 Software Recall Rev 1.0 to 1.2.

HS3-99SB2 Current Measurement Errors (Intermittent)

HS3-07SB1 Current Measurement Errors (Intermittent)

HS3-99SB1 Current Measurement Errors

All HS3 product was located and replacement software was issued. A 'Software Watchdog' was incorporated to prevent the processor from getting 'lost' and not have a reset. A starter was reported to 'Lockup' while in coast mode with the interlock enabled, thereby permitting exposures without rotation power.

HS3-99SB2 Current Measurement Errors

A 'JRC' brand 'LF347 amplifier' used on CB572 (Tube Select and Safety) has been determined to have low drive characteristics. The device caused Intermittent Current Measurement as well as Intermittent Safety Detection. Replace the device with another brand or contact the factory for replacements.

Models Affected:

HS3-R Serial Numbers 11-99001 to 11-99027

HS3-RQ Serial Numbers 13-99001 to 13-99003

HS3S-RQ Serial Numbers 15-99001 to 15-99007

HS3-07SB1 Current Measurement Errors (Intermittent)

The multiplexer U3 on CB572 (Tube Select and Current Measurement board) is a CD4053 chip. The 6502 microprocessor outputs do not reliably select the chip inputs because the voltages of the 6502 system are borderline for the cmos chip. Replace the CD4053 chip with 74HCT4053 as this chip compatible with the 6502 voltage levels. This problem took years to track down because sending out the CB572 and sometimes the CB574 (microprocessor board) solved the problem.

Models Affected (All HS3)

Recent Service Inquiries (Repair Issues)

I have compiled the following service tips from field calls during the last year or so.

Intermittent current measurement issues.

We have had a couple of units with bad rotor cable connecting plugs. Try replacing the connector.

Loss of rotor start current or Low Current may be caused by a faulty Power Relay Board (CB513).

Always perform 'Setup' after replacing the software or making any repairs which could affect the current draw.

The most reliable software is Version 3.0 or above (non Shimadzu) and 4.0 or above for Shimadzu.

Generator Noise affecting measurement. Version 3.02 (non Shimadzu) and 4.02 or above for Shimadzu

Processor fails to complete initialization sequence ('Testing Board Integrity' message is displayed.): 1. A very noisy line may prevent the initialization of the processor board. This problem was fixed with software version 2.42.

2010-2011: Intermittent or 'No Shifted Current': Very recently the 6 mfd phase shift capacitor has been failing. They become intermittent or open and on rare occasion, drop in value significantly. Put the starter in 'service' mode, and make a high speed rotation request. Measure the phase shift voltage to the stator (common to shifted) during acceleration. This voltage should be about 550 to 600VAC in high speed start. The starter will drop out of high speed rotation when the measurement fails so you may need to use an oscilloscope to view the voltage. Be sure to keep the scope off ground!
Another method to test for a bad 6 mfd capacitor might be to use low speed (the 6mfd and 25mfd capacitors are in parallel during low speed rotation). While the tube is rotating in low speed, pull the wire off the 6 mfd capacitor. If there is no voltage change to the shifted voltage (C-A voltage), then the capacitor is likely open.

Last Updated 02/14/2011