This document provides technical specifications for the Balboa Instruments GS520SZ spa control system. It includes the system model number, software version, and component part numbers. Wiring diagrams and DIP switch settings are provided for two different spa equipment setup configurations.

1. GS520SZ Tech Sheet
Balboa Instruments
System PN 55423-01
System Model # GS5-GS520SZ-RCA-3.0
Software Version # 43
EPN # 2808
Base PCBA - PN 55424-01
PCB GS500Z - PN 22015 Rev B
Base Panels
VL700S – PN 53811
VL701S (Serial Standard) – PN 53189
VL702S – PN 54652
Template used: 40599_N.pdf 05/07/2008
55423-01_B.pdf 08/30/2008
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2. System Revision History
System PN EPN Date Requested By Changes Made
55423-01 2808 08.28.2008 Balboa Software update to version 43.
55423-01 2808 09.29.2008 Balboa In setup 2 change 1-Spd P2 to 1-Spd P3.
55423-01 2808 09.30.2008 Balboa Clarify Circ Pump behavior
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3. Basic System Features and Functions
Power Requirements
Requires PCB Rev B.
System Outputs
Setup 1 (As Manufactured) Setup 2
(Stereo) (Stereo)
Optional Devices Optional Devices
Additional Options J71
J2A J1A
J1
J2
1
J18
J10
U4
J19
J12
J60 J7 J8 J44
1 1 1 1 1
J22
1
EXT RLY AUX F SEN A SEN B VAC J11
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4. Basic System Features and Functions
Any time you change a DIP Switch, other than A1, you must reset Persistent Power Up Display Sequence
Memory for your new DIP Switch Settings changes to take effect. If you do Upon power up, you should see the following on the display:
not reset Persistent Memory, your system may function improperly. Three numbers in a row, which are the SSID (the System Software
ID). The third display of these numbers is the Software Version,
To reset Persistent Memory: which should match the version of your system. For example, if these
Power down by disconnecting power source from spa. three numbers are , that is a VS511SZ at version 38.
Put a jumper across J43, covering both pins. (See illustration below) Displayed next is: “ ” (indicating the system is configured for
Power up by connecting power source to spa. a heater between 3 and 6 kW) or “ ” (indicating the system is
Wait until “ ” is displayed on your panel. configured for a heater effectively* between 1 and 3 kW).
Power down again. “ ” should appear for all VS models running at 240VAC.
Remove jumper from J43 (May also move to cover 1 pin only) “ ” should appear for all VS models running at 120VAC, as well
as all GS models. (*A heater which is rated at 4 kW at 240VAC will
Power up again.
function as a 1 kW heater at 120VAC.)
“ ” will appear to signal the start of Priming Mode.
About Persistent Memory and Time of Day Retention:
This system uses memory that doesn’t require a battery to store a variety of
At this point, the power up sequence is complete. Refer to the Reference
settings. What we refer to as Persistent Memory stores the filter settings,
Card for the VS or GS System model of your spa for information about how
the set temperature, and the heat mode.
the spa operates from this point on, including how to adjust the Time of
Day if using a Serial Deluxe style panel.
Persistent Memory is not used for Time of Day. Only models with a
Serial Deluxe panel installed (VS5xxDZ and GS5xxDZ) can display the
time. However, during power loss to the spa, the system will lose the
correct time, and reset to 12:00 PM when power is restored.
J43
TST RST
FUSE 20A 250V J47 J6 J43
J46
F7 J29
K6 J23 J50 PUMP OZONE
K1 J23 J29
F1 F5, F3A 250V J20
J20
J17/26
J6
E.GND
G
G
K5
J90
G C
C
C
FUSE 3A 250V
C
C
C
C
C
C
S1 TST
G
G
G
J50
W7
W4
G
G
G
J12
W1 K8 K5
F4 FUSE .3A 250V
SWITCHBANK A
T1 K9 W3
W2 K4 K1
SWITCHBANK A
J1 J1A
J10
J18
F2 U4
J13
J2A T0.25A 250V
NEUTRAL
WHT AC J1
J18
W1 J58 J57
1 2 3
K3 K3
U4 J12
K2
J2
VS100
P/N 22964_B MADE IN U.S.A.
J26 F4
Balboa
J43
© 2006
F2 LINE
K2
J13 TST RST
BLK AC
BALBOA INSTRUMENTS, INC. 2-SPD S1 J6 J43
J60 J22 J44 VS500Z EXT RLY
J6 J7 J8 J7 J8
E.GND
P/N 22972 REV D
J9
S1 TST EXT.
T AUX. F VAC MADE IN U.S.A
V
SWITCHBANK A RLY
L SEN. A SEN. B COPYRIGHT 2005 HEATER
A
SWITCHBANK A SEN. A SEN. B
J43 on VS5xxZ and VS300 Series Main Board Shown. J43 on VS100/GS100 Series Main Board Shown.
J43 on GS5xxZ Series is located in approximately the same position.
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5. Wiring Configuration and DIP Settings
Setup 1 (As Manufactured) HIPot Testing Note:
Disconnect slip terminal with green
(Stereo) wires from J90 prior to performing
HiPot test. Failure to disconnect may
cause a false failure of the test.
Reconnect terminal to J90 after
successful completion of HiPot test.
AV F7 F1 J13
J50 J29 J23 K6 K1 F10A 250V
OZONE PUMP 1 K9
F3A 250V
J52 J51 F6, T30A 480V
J
Audio Visual
G N
J46
Blower
2-Spd P1
1-Spd P1
Ozone
J47
CIRC. PUMP
K8
K5 J20
Circ Pump
N
J25
5 G N C9 Spa
N
N
G N
J32
2 Light
G
G
G F3
TB1 10VAC
10VAC
J17/26 J72
1 F4, T0.2A 250V OPT. BLWR/PUMP 2 J71
T1
J58
J2A J1A
2 J1
W2
J28
8
J2
3
J26
6
K3
1
J18
4 J43 J10
K4
U4
J57
F2
Balboa
J19
HTR2 J101 HTR1 00 K2 S1
W1 J90 J12
BALBOA INSTRUMENTS, INC. J60 J7 J8 J44
J6
GS5xxSZ mode
E.GND
GS500Z 1 1 1 1 1
COPYRIGHT 2007 Pb
Pb
MADE IN U.S.A. TST J22 1
P/N 22015_B SWITCHBANK A EXT RLY AUX F SEN A SEN B VAC J11
Heater rated @ 240V 3.0kW
3.0 kW J11 must be Jumpered
X-P332 CE
PN 55138 J7
J1
2-Spd P2
R
P/N 22909 REV B
W1
B
J6
W G
F30A 480V
WARNING: Main Power to system should be turned OFF BEFORE adjusting DIP switches.
WARNING: Persistent Memory (J43) must be RESET to allow new DIP switch settings to take effect. (See Persistent Memory page)
GS520SZ
SSID # Software
Wiring Color Key
J11 J12 3
Neutral (Common) AC Connections
100 3.0kW Special AC Connections
98 Heater 2 Line AC Connections
43 10 Volt Connections
A1, Test Mode OFF A6, 50 Hz 1
Relay Control Wires
A2, See Table 1 A7, J17/26 Disabled
Enabled
A3, N/A J43
A8, Degrees C Memory Board Connector Key
A9, See Circ Mode Table Reset
A5, A10, See Table 1
1 Typically Line voltage
2 Typically Line voltage for 2-speed pumps
Panel Button Assignments Panel Button Positions
3 Neutral (Common)
1=Mode 5=Pump 1 2 4 7
7 1 2 4
2=Temp Up 6=Pump 2 Ground
1 3 5 6
3=Temp Down 7=Unused
7=J17/26 5 6 4 3
Note flat sides in connector
4=Light
5 2
6 1
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6. Wiring Configuration and DIP Settings
Setup 2 HIPot Testing Note:
Disconnect slip terminal with green
wires from J90 prior to performing
HiPot test. Failure to disconnect may
cause a false failure of the test.
(Stereo) Reconnect terminal to J90 after
successful completion of HiPot test.
AV F7 F1 J13
J50 J29 J23 K6 K1 F10A 250V
OZONE PUMP 1 K9
F3A 250V
J52 J51 F6, T30A 480V
J
Audio Visual
G N
1-Spd P3
J46
2-Spd P1
1-Spd P1
Ozone
J47
CIRC. PUMP
K8
K5 J20
Circ Pump
N
J25
5 G N C9 Spa
N
N
G N
J32
2 Light
G
G
G F3
TB1 10VAC
10VAC
J17/26 J72
1 F4, T0.2A 250V OPT. BLWR/PUMP 2 J71
T1
J58
J2A J1A
2 J1
W2
J28
8
J2
3
J26
6
K3
1
J18
4 J43 J10
K4
U4
J57
F2
Balboa
J19
HTR2 J101 HTR1 00 K2 S1
W1 J90 J12
BALBOA INSTRUMENTS, INC. J60 J7 J8 J44
J6
GS5xxSZ mode
E.GND
GS500Z 1 1 1 1 1
COPYRIGHT 2007 Pb
Pb
MADE IN U.S.A. TST J22 1
P/N 22015_B SWITCHBANK A EXT RLY AUX F SEN A SEN B VAC J11
Heater rated @ 240V 3.0kW
3.0 kW J11 must be Jumpered
X-P332 CE
PN 55138 J7
J1
2-Spd P2
R
P/N 22909 REV B
W1
B
J6
W G
F30A 480V
WARNING: Main Power to system should be turned OFF BEFORE adjusting DIP switches.
WARNING: Persistent Memory (J43) must be RESET to allow new DIP switch settings to take effect. (See Persistent Memory page)
GS520SZ
SSID # Software
Wiring Color Key
J11 J12 3
Neutral (Common) AC Connections
100 3.0kW Special AC Connections
98 Heater 2 Line AC Connections
43 10 Volt Connections
A1, Test Mode OFF A6, 50 Hz 1
Relay Control Wires
A2, See Table 1 A7, J17/26 Disabled
Enabled
A3, N/A J43
A8, Degrees C Memory Board Connector Key
A9, See Circ Mode Table Reset
A5, A10, See Table 1
1 Typically Line voltage
2 Typically Line voltage for 2-speed pumps
Panel Button Assignments Panel Button Positions
3 Neutral (Common)
1=Mode 5=Pump 1 2 4 7
7 1 2 4
2=Temp Up 6=Pump 2 Ground
1 3 5 6
3=Temp Down 7=Unused
7=J17/26 5 6 4 3
Note flat sides in connector
4=Light
5 2
6 1
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7. DIP Switches and Jumpers Definitions
SSID 100 98 43 Base Model GS520SZ
DIP Switch Key
A1 Test Mode (normally OFF)
A2+A10 Control amp draw requirements (See Table 1) Table 1 # of Hi-Speed
A3 N/A (must be OFF) Pumps/Blower
A4 Aux Freeze (must be OFF) Before Heat Disabled
A5+A9 Pump 1 speeds and Circ Modes: A2 A10
A5 A9 Circ Mode Pump 1 Speed OFF OFF 0
OFF OFF Non-circ 2-speed ON OFF 1
ON OFF Circ "acts like Pump 1 low" (filters/polls/ect) 1-speed OFF ON 2
OFF ON 24 hours with 3°F shut-off 1-speed ON ON 3
ON ON 24 hours with 3°F shut-off 2-speed
A6 “ON” position: 50Hz operation Alert:
“OFF” position: 60Hz operation 2-speed Pump 2 is required, uses
A7 “ON” position: J17/26 Enabled for Blower or 1-speed Pump.* X-P332 CE expander board.
“OFF” position: J17/26 Disabled. To add Blower or 1-speed Pump 3,
A8 “ON” position: temperature is displayed in degrees Celsius use J17/26.
“OFF” position: temperature is displayed in degrees Fahrenheit
* Panel with button layout is not compatible when A7 is ON.
Jumper Key
J11 If using 3kW or higher wattage heater, jumper can be set in either position, but may perform better on Pins 1 and 2.
If using 2.5kW or lower wattage heater, jumper must be set on 1 Pin only.
J12 Factory set. DO NOT MOVE.
Jumper must be on Pins 1 and 2 for GS51xZ/GS52xZ/GS5xxSZ/GS5xxDZ software.
Jumper must be on Pins 2 and 3 for GS50xZ software.
J43 When jumper is placed on 2 pins during power-up, system will reset persistent memory.
Leave on 1 pin only to enable persistent memory feature.
WARNING:
Setting DIP switches incorrectly may cause abnormal system behavior and/or damage to system components.
Refer to Switchbank illustration on Wiring Configuration page for correct settings for this system.
Contact Balboa if you require additional configuration pages added to this tech sheet.
Panel Button Positions Aux Panel Information
7 1 2 2 4 7 Supports 2-button aux panel
5 6 4 3 1 3 5 6
VX20 5 6
5 2
6 1
4 3
Supports 4-button aux panel
Panel Button Assignments VX40S 5 6 7 4
1=Mode 5=Pump 1
2=Temp Up 6=Pump 2
3=Temp Down 7=J17/26 (when A7 is ON)
4=Light
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