User's Manual

044-05156 Rev C 46
The open collector circuit has a 10mA limitation. The interface also includes two auxiliary TTL signals. One is an
input and the other an output. The auxiliary output signal is a 74HC14 inverter output. The auxiliary signals have no
function at this time.
RECT6 signal represents the alarm status of the LVD controller.
PIN Description PIN Description
1 GND 6 Rectifier Fault 5
2 Rectifier Fault 1 7 Rectifier Fault 6 (LVD)
3 Rectifier Fault 2 8 Auxiliary TTL Input
4 Rectifier Fault 3 9 Auxiliary TTL Output
5 Rectifier Fault 4
4.9.4 Cabinet Alarms
4.9.4.1 Cabinet – Intrusion / AC Fault Interface (J19)
A DB15 Female connector provides the Cabinet intrusion and AC fault interface. The intrusion inputs are contact
closures from all of cabinet doors: front, rear, battery, and AC service. All Common contacts are tied to the system
ground. The Normally Closed contacts are pulled-up and passed to the micro-controller. A logic high signal signifies
an intrusion via an open door.
The AC power fault passes through to the DALI interface Common contact with reference to the BTS COMMON1.
An open contact signifies an AC fault. The AC fault signal is not processed.
PIN Description PIN Description
1 Ground 9 AC Door Common Contact
2 Front Door Normally Closed Contact 10 AC Alarm Normally Closed Contact
3 Front Door Common Contact 11 AC Alarm Common Contact
4 Rear Door Normally Closed Contact 12 No Connection
5 Rear Door Common Contact 13 No Connection
6 Battery Door Normally Closed Contact 14 No Connection
7 Battery Door Common Contact 15 No Connection
8 AC Door Normally Closed Contact
4.9.4.2 Cabinet Fan Control and Interface (J20)
Each of the cabinet fans has a sense signal with a 50% duty cycle square wave. The frequency of the square wave
signal is directly proportionate to the RPM of the fan. The speed of the fan is dependant on the applied control
voltage. The rotational speed of the fan is dependent on the applied DC voltage to the control input of the fan. The
control function is supported by a micro-controller.
The fan control ports will be forced to 0% PWM if the front door is sensed open. The fan status will latch to the
current state and all fault times will be halted and saved. Upon the sensed door closure the fan sense routine will
continue where it left off.
The temperature information is derived from:
o The DLNA temperature analog input.
o The MCPA serial interface.
o The SIM internal temperature analog input.
The highest temperature measurement among these devices determines the fan setting. All four-fan control ports
function identically with each other. The PWM outputs do not increment or decrement > 1 step per minute.
If the +27V input is < 24V, the temperature thresholds increase by +10°C. If the voltage is less than 24V the battery
back-up system is assumed the primary DC source and the system will operate at an accelerated temperature to
reduce the current draw of the cabinet fans in an attempt to extend battery life.