Editing PDP-11/70 Power Supply Service (section)

== AC power: the 861 power controls ==
{| class="wikitable styled-table" style="width:70%; text-align:center;"
|+ '''861-D and 861-E (EK-11070-MM-002, Table 4-2)'''
! !! 861-D !! 861-E
|-
| Supply || 90–132 V phase to neutral, three-phase wye || 180–264 V phase to neutral (312–458 V phase to phase)
|-
| Current || 24 A per phase || 15 A per phase
|-
| Full load || 8,640 VA || 10,800 VA
|-
| Input breaker || 30 A, delayed action, manual reset || 15 A
|-
| Outlets || 14 (10 switched, 4 unswitched); 15 A each, 24 A per phase || 14; 12 A each, 15 A per phase
|-
| Thermal switch || colspan="2" | Opens at 71.1 °C, resets at 49 °C
|}
<ref name="mm861" />
The switched outlets follow the console switch through the remote control bus, and are cut if the thermal switch in the processor mounting box or the one on the side of the 861 trips; the memory cabinet's 861 follows the processor cabinet's.<ref name="mm421" /> DEC's 861 has no adjustments or fuses. Its preventive maintenance is cleaning and inspection, a check of the thermal switch by heating its sensing element while the controller runs, and a check of emergency shutdown by connecting pins 3 and 2 of the remote switching control bus.<ref name="mm45" /> DEC lists three failure modes:<ref name="mm45" />
* No output with the breaker tripped: a faulty breaker, a low-resistance load, or a failed component inside the controller.
* No output with the breaker not tripped: bad cable connections, an open component in the line filter, a relay fault or a faulty breaker.
* No control: bad cables, secondary breakers, relays, diodes or the thermal switch T1. Set the LOCAL/OFF/REMOTE switch to LOCAL: if the switched outlets still do not come on, the fault is inside the controller; if they do, check the control signals from outside.