HS3 Service Bulletins
HS3-99SB1 Software Recall Rev 1.0 to 1.2.
HS3-99SB2 Current Measurement Errors (Intermittent)
Current Measurement Errors (Intermittent)
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.
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
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
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
- 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
- Generator Noise affecting measurement. Version 3.02 (non Shimadzu) and 4.02 or above for
- Processor fails to complete initialization sequence ('Testing Board Integrity' message
- 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