Last lacing and start of reinstallation in sequencer box

FINAL LACING COMPLETED

IBM lacing is done so well that you can tell immediately which screw on a terminal block that each wire should connect to. The section that brought the wires to the SMS card (power sequence logic) is well laced enough that there is no chance of confusion. The wires run to socket connections A, C, E, F, G, K, L, M, N and Q, from right to left when viewing the socket from the side of the machine. The lacing separates each wire so that you can't mistake one for another. 

That set a high bar for me to match as I relaced the bundle. I worked hard to provide the same unambiguous exit of each wire from the bundle to ensure that connecting them to the terminal blocks will be quick and easy. 

It didn't look as good as the IBM work, but it did hold the wires together and get all the terminal rings at the proper point for attachment. 

TRANSFORMER T1 MOUNTED AND WIRED TO TB7

I mounted T1 on the left side of the box and connected the wires to the appropriate terminals on TB-7 on the bottom. It has the proper jumper set up for 230V operation. It is ready to go, providing 24VAC to the rest of the circuitry. 

BUNDLE PLACED IN THE BOX

The bundle of wires has groups of wires exiting through two holes in the box. One opening at the upper left feeds the wires out to connect to TB-3 which is a horizontal terminal block on the left outside of the box. The other opening in the rear feeds wires to TB-1, a horizontal terminal block on the outside rear of the box plus wires to the SMS card. 

The bundle runs from the top to the bottom along the left side, feeding connections to vertical terminal block TB-2 inside, then it splits. A section runs along the front panel to connect to the fuse holders and time delay relay. The remainder runs along the bottom of the box, connecting the contactor, TB-7 terminals and the circuit breaker. Another bifurcation delivers a small set of wires to the convenience outlet and CE switch on the right side of the box. 

The bundle them runs vertically up to connect the three relays mounted on a shelf, as well as passing out of the rear hole to connect to the SMS card and TB-1. With the bundle positioned in this way, ring terminals are available directly in front of each component or terminal block that needs to be connected.

CONTACT CORROSION CLEARED ON FOUR RELAYS

I used a burnisher and some deoxidizing spray to clean the contacts on relays R1, R2, R3 and the time delay relay TD1. I discovered that relay R3 had its armature rusted to the frame due to urine contamination. It wouldn't move down at all. I worked on it for a while and it is slightly better but this relay may not work. 

The relay feeds power to the convenience outlets when the 24VAC is on, even if the machine is otherwise powered down. The impact if this doesn't work is that the convenience outlets will be dead, but the rest of the machine will work properly. 

I can try to free up the armature later, or find a suitable replacement relay, or just wire around the relay so that the convenience outlets are always on when the circuit breaker is turned on, even if the EPO button (red Emergency button) is pulled out or the CE switch is turned to off. If I do the latter, then I would affix a big warning sign by the convenience outlet about the presence of power even with EPO and CE switch activation. 

MOUNTING ALL COMPONENTS AND WIRING THEM TO THE BUNDLE

All the parts inside the box are now mounted and wired to the bundle. The relay R3 is in place although it might not work as I mentioned in the paragraph above. The wire bundles are passed through the holes to connect to the SMS card, to TB1 and to TB3. 

TWO OTHER HOLES BRING WIRES INTO THE BOX

One hole at the bottom left side of the rear of the box delivers the primary power from the line filter (and building AC plug). Another on the left upper side of the rear of the box has wires which feed various peripheral devices with AC. These enter through the hole and are attached to TB-2 inside the box. 

I didn't finish connecting those wires to TB2. The power supply feeds are connected but the convenience outlet power to the 1132 and the 1442 are not yet connected, nor is the 115VAC for the peripherals that connect via SMS cards - disk drive and typewriter for this system. 

CAREFUL CHECKING WITH EACH CONNECTION

Every time I connect a wire to a screw or component, I beep out the connection to be certain that it is the proper wire. This takes time but is important so that I don't make a mistake that blows a fuse or worse.