Instructions

42
2. Setting the units as Master or Slave
3. Master and Slave units default operation
4. CURRENT display accuracy
5. To release units from Slave mode
a) Depress and hold the FINE button for 3 seconds. The Master/Slave configuration will be
displayed on the Current Display. Rotate the CURRENT encoder to obtain the desired mode.
Refer to Table 5-4 for the CURRENT display and modes of operation.
b) When the desired configuration is obtained, depress and release the FINE button or wait
approx. 5 seconds.
a) When a unit is programmed to Slave mode it enters the Remote mode with Local Lockout. In
this mode, the front panel controls are disabled to prevent accidental setting change (refer to Sec.
7.2.7 for details).
b) The Slave units parameters will automatically set the following:
*Output voltage to approximate. 102% of rated output voltage.
*Programmed Current to zero.
*UVL to zero volts
*OVP to its maximum value
*AST On
*OUT On
*Foldback protection Off
c) The Master and Slave modes are stored in the power supply EEPROM when the AC power is
Turned off. The system will return to the Master/Slave mode upon re-application of AC power.
In the advanced parallel mode, the total current is programmed and reported by the Master. In
this method, the CURRENT display accuracy is 2%+/- 1 count. In cases that higher accuracy is
required, it is recommended to use the basic parallel operation mode.
Slave units can be released using the following procedure:
a) Depress FINE button for 3 seconds. The Master/Slave configuration will be displayed on the
CURRENT display.
b) Select H1 mode using the CURRENT encoder.
c) Depress FINE button again or wait 5 seconds.
d) Turn the AC power Off to store the new setting.
+V
-V
+V
-V
+S
+LS
-S -LS
+S
+LS
-S -LS
MASTER
POWER SUPPLY
SLAVE#1
POWER SUPPLY
J1-25
J1-12 COM
J1-10
J1-23
P
IPGM
IPGM_RTN
To J1-23
SLAVE#2
POWER SUPPLY
To J1-10
SLAVE#2
POWER SUPPLY
Fig.5-4: Parallel connection
with local sensing
+
-
LOAD
As short as possible
Twisted
pair
J1-8
J1-12
CAUTION
Make sure that the connection between -Vo terminals is reliable to avoid disconnection during
operation. Disconnection may cause damage to the power supply.
CURRENT Display
H1
H2
H3
H4
S
Operating Mode
Single supply (default)
Master supply with 1 Slave supply
Master supply with 2 Slave supplies
Master supply with 3 Slave supplies
Slave supply
Table 5-4: Setting mode of operation
43
Fig.5-5: Parallel operation with Remote sensing
With local sensing it is important to minimize the wire length and resistance. Also the
positive and negative wire resistance should be close as possible to each other to achieve
current balance between power supplies.
NOTE
5.16 DAISY-CHAIN CONNECTION
It is possible to configure a multiple power supply system to shut down all the units when a fault
condition occurs in one of the units. When the fault is removed, the system recovers according to its
setting to Safe start mode orAutomatic restart.
Setup switch SW1 position 5 should be set to its Down position to enable the Daisy-chain operation.
Other SW1 positions can be set according to the application requirements.
If a fault occurs in one of the units its PS_OK signal will be set to low level and the display will indicate
the fault. The other units will shut off and their display will indicate "SO”. When the fault condition is
removed, the units will recover to their last setting according to their Safe start orAuto-restart setting.
Fig.5-6 shows connection of three units, however the same connection method applies to systems
with a larger number of units.
Fig.5-6: Daisy-chain connection
POWER SUPPLY
#1
J1-2,3
J1-16
J1-16
J1-16
J1-15
PS_OK
POWER SUPPLY
#2
J1-2,3
J1-15
PS_OK
SO
POWER SUPPLY
#3
J1-2,3
J1-15
PS_OK
SO
SO
IF_COM
IF_COM
IF_COM
5.17 FRONT PANEL LOCKING
The front panel controls can be locked to protect from accidental power supply parameter change.
Press and hold PREV button to toggle between “Locked front panel” and “Unlocked front panel”.
The display will cycle between “LFP” and “UFP”. Releasing the PREV button while one of the
modes is displayed, selects that mode.
In this mode, the front panel controls are enable to program and monitor the power supply
parameters.
In this mode the following front panel controls are disabled:
- VOLTAGE and CURRENT encoders.
- FOLD button.
- OUT button.
The power supply will not respond to attempts to use these controls. The VOLT display will show
“LFP” to indicate that the front panel is locked.
OVP/UVL button is active to preview the OVP and UVL setting.
Use PREV button to preview the output voltage and current setting or to unlock the front panel.
5.17.1 Unlocked front panel
5.17.2 Locked front panel
MASTER
POWER SUPPLY
SLAVE#1
POWER SUPPLY
J1-25
J1-10
P
IPGM
J1-12 COM
J1-23
IPGM_RTN
Twisted
pair
+V
-V
+
V
-V
+S
-S
+
-
LOAD
As short as possible
Twisted
pair
+S
-S
+S
-S
Twisted
pair
+S
-S
+S
-S
J1-8
J1-12
To J1-10
SLAVE#2
POWER SUPPLY
To J1-23
SLAVE#2
POWER SUPPLY
CAUTION
Make sure that the
connection between -Vo
terminals is reliable to
avoid disconnection
during operation.
Disconnection may cause
damage to the power
supply.