The Multiboard electronics, sometimes referred to old electronics are usually used in the MKII and MKIV Brewers. Some of the earlier MKIII brewers may also be running the multiboard electronics. The multiboard electronics consist of the primary power supply¹ (PPS), secondary power supply, Card cage boards, and the heatsink.
¹Note, both multiboard and single board electronics both have an PPS, however the multiboard uses a 24V/15V/5V power supply while the single board electronics uses 24V/12V/5V power supply. The latest brewer's produced by Kip and Zonen (around Brewer # 250) uses the TDK-Lambda NV175 series power supply. The single Electronics board uses NV1-4G5TT, where the multiboard uses the NV14G5FF.
There are 7 cards that are needed for a brewer to be in operation. The following list is the order the boards are in from top to bottom.
For Diagnostics purposes, the minimal amount of boards required to communicate to the brewer from a computer is just the Microprocessor/RCA board and the Photon Counter Board. All the other boards can be removed. This will help diagnose if there is a bad board causing communication issues.
Note: These wiring harness are based on CBSN brewer setup. Your brewer wiring may vary slightly
Q: What are the differences between new vs old temperature circuit on the clock board?
A: Note the resistors on the top right of the boards below (New Vs Old). In the new temperature circuits, some resistors have been replaced with a jumper wire.

Q: How do I find out what LED sensor is active?
A: Depending on what you're looking for, you can use one of the 3 commands in MM GET,800GET,544GET,1056. This will yield the following
| Bits | GET,800 | GET,544 | GET,1056 |
|---|---|---|---|
| 0 | CW Switch Pressed | Slitmask @ 7 | |
| 1 | CCW Switch Pressed | Slitmask @ 0 | |
| 2 | CW AZ Sensor Blocked | Mic1 @ Max WL(Mirror side) | |
| 3 | CCW AZ Sensor Blocked | Mic1 @ min WL(Bulkhead side) | |
| 4 | ZE Sensor Blocked | Iris Fully open | |
| 5 | FW3 Sensor Blocked(Mic2 @ Max wl in MKIII) | FW3 Sensor Blocked in MKIII | Iris Fully Open |
| 6 | Down Switch Pressed | ||
| 7 | Up Switch Pressed |