PS-20 Power Supply User Manual 9350-6786-100 Rev F OCT 2009
PROPRIETARY NOTICE SHIPPING TO THE MANUFACTURER The product information and design disclosed herein were originated by and are the property of Bosch Security Systems, Inc. Telex reserves all patent, proprietary design, manufacturing, reproduction, use and sales rights thereto, and to any article disclosed therein, except to the extent rights are expressly granted to others. All shipments of product should be made via UPS Ground, prepaid (you may request from Factory Service a different shipment method).
Important Safety Instructions 1. Read these instructions. 2. Keep these instructions. 3. Heed all warnings. 4. Follow all instructions. 5. Do not use this apparatus near water. 6. Clean only with dry cloth. 7. Do not block any ventilation openings. Install in accordance with the manufacturer’s instructions. 8. Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat. 9.
Table of Contents IMPORTANT SAFETY INSTRUCTIONS ..........................................................................................................................................III INTRODUCTION ........................................................................................................................................ 3 Description .............................................................................................................................................................
CHAPTER 1 Introduction Description The PS-20 is a complete and independent power supply, with the added features of 2- and 4-channel operation, monitoring, 2channel program input, audio linking and three (3) modes of operation: RTS 2-channel, RTS 4-channel and Clear-Com mode. The PS-20 features two (2) channels of communication where both channels are wet, meaning there is power on each channel (RTS 2-channel mode).
Features Selectable Mode Operation - The PS-20 is selectable between RTS 2-channel, RTS 4-channel and ClearCom mode. Audio Linking - Audio Linking allows you to connect up to two (2) PS-20s with a standard stereo cable. There is an Audio Link for CH1 and CH2 and an Audio Link for CH3 and CH4 connection for two way communications. To learn how to configure Audio Linking, Figure 2, “Audio Linking Two-way communication configuration.
Reference View FIGURE 1. PS-20 Reference View 1. Channel Indicator LEDs - Provides a visual indication of the channel DC power. A green LED displays for normal operation and a red LED displays when there is an overload or short circuit. 2. Monitor Output - Front panel connection for system administrator to listen (can talk as well) to channel 1, channel 2 or both. This is a 3-pin XLR (male). In Clear-Com mode, only channel one (1) is heard. A user station or beltpack is required to use this feature.
Specifications General AC Input Input Voltage: 90 to 240 VAC, 50 to 60 Hz Output Voltage: 28 VDC to 32 VDC Output Current: 1.80 Amps Maximum per channel Termination Impedance: Selectable 200 Ω / 400 Ω Ripple: < 0.2 V Program Input Levels: Nominal +2 dBu Balanced, High Impedance >10 kΩ Two-Wire Output Levels: Nominal 30 VDC Unbalanced, selectable 200 Ω / 400 Ω Monitor Output: Nominal Gain of 0 dB for 1000 mVRMS input level on the program input. 30 VDC nominal, 100 mA maximum.
Installation Mechanical Installation The PS-20 Power Supply can be rack mounted or used free standing. For rack configurations, see Figure 7, “Rack Mount Configurations for the PS-20.,” on page 13. Allow room for cable connections. Electrical Installation Connecting Intercom Stations NOTE: When connecting intercom stations, do not exceed the power supply capacity, either for channel 1, channel 2 or both. Power supply capacity is graphically illustrated in Figure 3 on page 9.
FIGURE 2. Audio Linking Two-way communication configuration. Program Inputs A program source may be connected to the PROGRAM INPUT connector on the rear panel. Pin assignments are as follows: Pin 1 = common/ground Pin 2 = balanced audio +input Pin 3 = balanced audio -input To connect an unbalanced program source, do the following: 1. Connect pin 3 to pin 1. 2. Connect program ground to pin 1 and program + to pin 2. AC Power Plug the AC power cord into the PS-20 and into an AC mains outlet.
FIGURE 3.
Channel Configuration The PS-20 is capable of three different modes of operation, RTS-TW 4-channel mode, RTS-TW 2-channel mode, and Clear-Com 2-channel mode (see Figure 4). FIGURE 4.
FIGURE 5.
Termination Impedance When connecting two (2) channels on a PS-20, the termination switch must be set to 400Ω to account for double termination. By setting the termination impedance at 200Ω over two (2) channels, the power load would decrease to 100Ω (1/200 + 1/200 = 2/200 = 1/100). However, by setting the termination switch to 400Ω when operating over two (2) channels the impedance to each channel is increased to 200Ω (1/400 + 1/400 = 2/400 = 1/200).
FIGURE 7. Rack Mount Configurations for the PS-20.
Configuration Diagrams FIGURE 8.
CHAPTER 2 Operation and Maintenance Power-up Indications Turn on the Power switch. During normal operation, the two (2) CHANNEL STATUS indicators light green. Fault Indications If there is a fault on a channel, the CHANNEL STATUS indicator for that channel turns red. Possible causes of a fault include: • • • • over voltage over current short circuit to ground severe brown-outs Monitor Output Use the monitor output to monitor channel 1, channel 2, or both channels at the same time.
Termination Impedance Switch Termination Impedance is necessary when two (2) channels of power are connected (whether between two (2) PS20s, or on the same unit). When connecting channels, the termination switch should be set at 400Ω, so it equals 200Ω on each channel. For more information on termination impedance, see “Termination Impedance” on page 12.
APPENDIX A PS-20 Quick Start NOTE: This quick start is to be used to get your PS-20 unit initially set and running. Further configuration may be needed for more advanced operation. On the back of the PS-20 unit: NOTE: On the front of the PS-20 unit, verify the Power Switch in turned off. 1. Connect the supplied power cord to the unit, and then plug the unit into the desired power outlet. 2.
