True to the Music
Radial Engineering Ltd.
Workhorse User Guide
7
Power Supply and Capacity
The Workhorse employs a universal power supply that will
automatically convert the various voltages used around the world
and regulate them before sending the power to the Workhorse. A
standard male IEC/EIN power input connector makes it easy to
travel as you need only change the cable to suit the local power
connector type.
The Workhorse does not have a power switch. As soon as you
connect the 5-pin XLR from the external supply to the Workhorse
it will be activated. Two front panel LEDs in the master section will
illuminate as soon as power is established. These indicate 48V
Phantom power is available and the +/-16V power supply for the
modules is active.
1
2
3
4
5
-16VDC
COM
+48VDC
+16VDC
COM
48V PHANTOM
+16V / -16V
The Workhorse power supply is a 1600 milliamps (mA) external
‘brick’ that provides 48 volts for phantom power and the required +/-
16 volts to supply each module. Pin-15 on the card-edge connector
provides phantom power. Turning phantom power on or off is module
dependent. So for instance if you plug in a mic preamp, it will normally
be set up to feed the phantom power from the Workhorse supply
to the microphone input thus enabling you to send +48V phantom
power to a condenser microphone or active DI. For modules such
as dynamic processors or EQs that do not use phantom power, the
module simply ignores pin-15 as if it were not there.
Unlike some 500 series racks that are ‘power limited’, the Workhorse
pools the available current so that the user can confi gure the system
based on his or her requirements. The 1600 milliamps are fi rst
divided whereby 400 milliamps are reserved for the master mix
section. This leaves 1200 milliamps that can be shared among the 8
module slots and supplied via pins 12, 13 and 14.
EXTERNAL POWER SUPPLY
ON
ON
MONO
2
3
41
LEVEL
CLIP
PAN
Made in Canada
LEVEL
ON
6
78
5
LEVEL
MAIN
MON
48V PHANTOM
+16V / -16V
LEVEL
CLIP
PAN
ON
LEVEL
CLIP
PAN
ON
LEVEL
CLIP
PAN
PAN PANPANPAN
ON
LEVEL
CLIP
LEVEL
ON
LEVEL
CLIPON
LEVEL
CLIPON
LEVEL
CLIPON
1
2
3
4
5
-16VDC
COM
+48VDC
+16VDC
COM
OUTPUT: +/-16V and
+48V Phantom (1600mA)
INPUT: 100V - 240V
(50 ~ 60 Hz)
CARD SLOTS: 1200mA
MIXER:
400mA
1 2 3 4 5 6 7 8
So for instance if you have a couple of power-hungry tube preamps
in slots 1 and 2 that require 250 milliamps of current, you still have
700 milliamps of current left to power the other six slots. Considering
most 500 series modules use between 40 and 80 milliamps of
current, it is unlikely you will ever exceed the Workhorse’s available
power. Note: The original API spec calls for 130mA on each slot.
The Workhorse not only exceeds this (150mA when current draw is
divided equaly between eight card slots) but allows you to distribute
the available power as needed.
Single Slot Modules Double Slot Modules
1 Mic Preamp 80mA 1 Tube Mic Pre 250mA
2 Equalizer 60mA 2
3 Compressor 60mA 3 Tube Limiter 250mA
4 Gate 60mA 4
5 Mic Preamp 80mA 5 Tube Mic Pre 250mA
6 Equalizer 60mA 6
7 Compressor 60mA 7 Tube Limiter 250mA
8 Gate 60mA 8
TOTAL DRAW 520mA TOTAL DRAW 1000mA
Installing The Workhorse
The Workhorse can be either mounted in a standard IEC 19 inch
rack system or placed on the desktop with the user installed rubber
feet that are included in the packaging.
The Workhorse is 19” wide, 7” deep and uses three standard vertical
rack spaces or 5.25”. The total rack depth needed for installation is
11” (280mm) to accommodate rear panel cable connectors. It is a
good idea to provide some means of support and strain relief for the
cable bundle connecting to the rear panel.
3RU
11”
Installing Modules In The Workhorse
Modules slide into the Workhorse card slots and make contact with
the card edge connector on the inside rear plane. Once in place,
modules are fastened using two 4/40 thread machine screws.
