Section VI
Control Interface Details
006-0006504 02/27/18
Rev R
45 of 56
UPS-3000 Guide
www.synqor.com
Digital Input/Output Control Signals
There are 2 input and 5 output digital signals available on the User I/O female high-density DB15
connector. The pin assignments and functions of these digital I/O signals are as follows:
Signal
Pin Number
Function
+5V
8
Load must be less than 35mA. Bias voltage with minimal current
drive usable as a pull-up voltage for the open collector output
signals (100Ω source resistance)
GND
4 and 5
Ground reference for all digital inputs and outputs
LOW_BATT
6
Open collector* output where “low” indicates battery charge
level is <10%
ACIN_GOOD
7
Open collector* output where “low” indicates AC Input voltage is
within range
ON_BATT
9
Open collector* output where “low” indicates the UPS is drawing
power from its battery
OUT_OK
14
Open collector* output where “low” indicates AC Output voltage
is within range
OVER_TEMP
15
Open collector* output where “low” indicates that the UPS is at
or above its maximum temperature
REMOTE_START
12
Drive this line “high” with ≥ 5mA to enable the UPS outputs
SHUTDOWN
13
Drive this line “high” with ≥ 5mA to disable the UPS outputs
*with an internal 50 kΩ Pull-up Resistor to 5V and ESD Protection Diodes.
RS232 Serial Interface
The same User I/O female high-density DB15 connector also provides for an RS232 interface
between the UPS and the host/system computer. The interface has a 115.2k baud with eight
data bits, no parity bit and one stop bit. The pin assignments and functions for this RS2332
interface are as follows:
Signal
Pin Number
Function
GND
4 and 5
Ground reference for RX and TX signals
RX
3
RS232 DCE/UPS Device Receive signal
TX
2
RS232 DCE/UPS Device Transmit signal
