BA11-A mounting box - Revision history

Ethan: Removed erroneous reference to available PSUs from previous edit.

2025-12-19T17:12:48Z

Removed erroneous reference to available PSUs from previous edit.

Ethan: Added info that there are two Power Distribution boards depending on which CPU/PSU is installed

2025-12-19T17:08:12Z

Added info that there are two Power Distribution boards depending on which CPU/PSU is installed

Jnc: New cat

2023-07-11T01:07:34Z

New cat

Jnc: Avoid dab

2022-09-20T00:26:17Z

Avoid dab

Jnc: +P/S details, FMPS, manual

2022-01-16T00:53:36Z

+P/S details, FMPS, manual

Jnc: /* Power connections */ rm dup linkage

2020-01-21T15:25:50Z

‎Power connections: rm dup linkage

Jnc: A good start

2020-01-21T15:24:16Z

A good start

New page

The '''BA11-A mounting box''' is a 10-1/2" [[mounting box]]; the terminal variant code notwithstanding, it is just about the last in the line of [[BA11 mounting boxes]]. It was introduced with the [[PDP-11/44]], and was also used with the [[PDP-11/24]] and [[VAX-11/730]]. Unusually for [[PDP-11]]s, its integral [[power supply]] provided +12V [[direct current|DC]], used as that time for [[Metal Oxide Semiconductor|MOS memory]].

It came with the [[H7140 power supply]], mounted at the rear of the box. There were four main variants, depending on the input [[alternating current|AC]] [[voltage]], and details of the secondary output: the -AA and -DA were 120V input, the -AB and -DB were 240V input.

Maximum power was 1350W with maximum load applied; it could provide 120A of +5V, and 10A of [[refresh]] +5V power to MOS memory; 3A of +15V, 3A of -15V; and 5A of +12V, 1A of -12V.

The H7750 battery backup unit, which provided refresh power to MOS memory mounted in the unit during brief power outages, was optional.

==Power connections==

[[Image:1144Power.jpg|300px|thumb|right|PDP-11/44 setup]]

The BA11-A does not use only the standard [[DEC power distribution connectors]]; it also provided special connections on [[bus bar]]s in its power supply, and in some applications (e.g. the [[KD11-Z CPU]]), the CPU's [[backplane]] uses unique [[Flexprint cable]]s for power, which go to the special connections (see image).

For backplanes which did not have the Flexprint cables (e.g. that of the [[PDP-11/24]]'s CPU), a special 'Power Distribution Board' (part # 54-13815) mounts to the bus bars and provides the needed connectors.

[[Category: DEC Hardware]]

@@ Line 3: / Line 3: @@
 Unusually for [[PDP-11]]s, its integral [[power supply]] also provided +12V/-12V [[direct current|DC]], used for the [[MS11-M MOS memory]]'s [[Metal Oxide Semiconductor|MOS]] memory [[integrated circuit|chips]].
-It came with the [[H7140 Power Supply]] ([[PDP-11/44]]) or [[H777 Power Supply]] ([[PDP-11/24]]), mounted at the rear of the box. There were four main variants, depending on the input [[alternating current|AC]] [[voltage]], and details of the secondary output:
+It came with the [[H7140 Power Supply]], mounted at the rear of the box. There were four main variants, depending on the input [[alternating current|AC]] [[voltage]], and details of the secondary output:
 {| class="wikitable"

@@ Line 3: / Line 3: @@
 Unusually for [[PDP-11]]s, its integral [[power supply]] also provided +12V/-12V [[direct current|DC]], used for the [[MS11-M MOS memory]]'s [[Metal Oxide Semiconductor|MOS]] memory [[integrated circuit|chips]].
-It came with the [[H7140 Power Supply]], mounted at the rear of the box. There were four main variants, depending on the input [[alternating current|AC]] [[voltage]], and details of the secondary output:
+It came with the [[H7140 Power Supply]] ([[PDP-11/44]]) or [[H777 Power Supply]] ([[PDP-11/24]]), mounted at the rear of the box. There were four main variants, depending on the input [[alternating current|AC]] [[voltage]], and details of the secondary output:
 {| class="wikitable"
@@ Line 27: / Line 27: @@
 The BA11-A does not use only the standard [[DEC power distribution connectors]]; it also provided special connections on [[bus bar]]s in its power supply, and in some applications (e.g. the -11/44's [[KD11-Z CPU]]), the CPU's [[backplane]] uses unique [[Flexprint cable]]s for power, which go to the special connections (see image).
-For backplanes which did not have the Flexprint cables (e.g. that of the -11/24's CPU), a special 'Power Distribution Board' ([[DEC part number]] 54-13815) mounts to the bus bars and provides the needed connectors.
+For backplanes which did not have the Flexprint cables (e.g. that of the -11/24's CPU), including the [[DD11-DK]], [[DD11-CK]], [[RK11-D]], etc., a special 'Power Distribution Board' ([[DEC part number]] 54-13815 for the 11/24 or 54-13632 for the 11/44) mounts to the bus bars and provides the needed Molex connectors.
 ==External links==

← Older revision		Revision as of 01:07, 11 July 2023
Line 37:		Line 37:
	* [https://www.pdp-11.de/index.php/knowledge-base/fan-overhaul/ Fan Overhaul BA11-A]		* [https://www.pdp-11.de/index.php/knowledge-base/fan-overhaul/ Fan Overhaul BA11-A]

−	[[Category: DEC ~~Hardware~~]]	+	[[Category: DEC Mounting Boxes]]

@@ Line 17: / Line 17: @@
 |}
-Maximum power was 1350W with maximum load applied; it could provide 120A of +5V, and 10A of [[refresh]] +5V power to MOS memory; 3A of +15V, 3A of -15V; and 5A of +12V, 1A of -12V or -15V.
+Maximum power was 1350W with maximum load applied; it could provide 120A of +5V, and 10A of [[memory refresh]] +5V power to MOS memory; 3A of +15V, 3A of -15V; and 5A of +12V, 1A of -12V or -15V.
 The [[H7750 Battery Backup Unit]], which provided refresh power during brief power outages to MOS memory mounted in the BA11-A, was an option.

@@ Line 1: / Line 1: @@
-The '''BA11-A mounting box''' is a 10-1/2" [[mounting box]]; the terminal variant code notwithstanding, it is just about the last in the line of [[BA11 mounting boxes]]. It was introduced with the [[PDP-11/44]], and was also used with the [[PDP-11/24]] and [[VAX-11/730]]. Unusually for [[PDP-11]]s, its integral [[power supply]] provided +12V [[direct current|DC]], used as that time for [[Metal Oxide Semiconductor|MOS memory]].
+The '''BA11-A mounting box''' is a 10-1/2" [[mounting box]]; the terminal variant letter notwithstanding, it is just about the last in the line of [[BA11 mounting boxes]]. It was introduced with the [[PDP-11/44]], and was also used with the [[PDP-11/24]] and [[VAX-11/730]].
-It came with the [[H7140 power supply]], mounted at the rear of the box. There were four main variants, depending on the input [[alternating current|AC]] [[voltage]], and details of the secondary output: the -AA and -DA were 120V input, the -AB and -DB were 240V input.
+Unusually for [[PDP-11]]s, its integral [[power supply]] also provided +12V/-12V [[direct current|DC]], used for the [[MS11-M MOS memory]]'s [[Metal Oxide Semiconductor|MOS]] memory [[integrated circuit|chips]].
-Maximum power was 1350W with maximum load applied; it could provide 120A of +5V, and 10A of [[refresh]] +5V power to MOS memory; 3A of +15V, 3A of -15V; and 5A of +12V, 1A of -12V.
+It came with the [[H7140 Power Supply]], mounted at the rear of the box. There were four main variants, depending on the input [[alternating current|AC]] [[voltage]], and details of the secondary output:
-The H7750 battery backup unit, which provided refresh power to MOS memory mounted in the unit during brief power outages, was optional.
+{| class="wikitable"
 ==Power connections==
@@ Line 13: / Line 27: @@
 The BA11-A does not use only the standard [[DEC power distribution connectors]]; it also provided special connections on [[bus bar]]s in its power supply, and in some applications (e.g. the -11/44's [[KD11-Z CPU]]), the CPU's [[backplane]] uses unique [[Flexprint cable]]s for power, which go to the special connections (see image).
-For backplanes which did not have the Flexprint cables (e.g. that of the -11/24's CPU), a special 'Power Distribution Board' (part # 54-13815) mounts to the bus bars and provides the needed connectors.
+For backplanes which did not have the Flexprint cables (e.g. that of the -11/24's CPU), a special 'Power Distribution Board' ([[DEC part number]] 54-13815) mounts to the bus bars and provides the needed connectors.
 [[Category: DEC Hardware]]

@@ Line 11: / Line 11: @@
 [[Image:1144Power.jpg|300px|thumb|right|PDP-11/44 setup]]
-The BA11-A does not use only the standard [[DEC power distribution connectors]]; it also provided special connections on [[bus bar]]s in its power supply, and in some applications (e.g. the [[KD11-Z CPU]]), the CPU's [[backplane]] uses unique [[Flexprint cable]]s for power, which go to the special connections (see image).
+The BA11-A does not use only the standard [[DEC power distribution connectors]]; it also provided special connections on [[bus bar]]s in its power supply, and in some applications (e.g. the -11/44's [[KD11-Z CPU]]), the CPU's [[backplane]] uses unique [[Flexprint cable]]s for power, which go to the special connections (see image).
-For backplanes which did not have the Flexprint cables (e.g. that of the [[PDP-11/24]]'s CPU), a special 'Power Distribution Board' (part # 54-13815) mounts to the bus bars and provides the needed connectors.
+For backplanes which did not have the Flexprint cables (e.g. that of the -11/24's CPU), a special 'Power Distribution Board' (part # 54-13815) mounts to the bus bars and provides the needed connectors.
 [[Category: DEC Hardware]]