MEETING NEW POWER DEMANDS Uninterruptible Power Supplies
Demand for Longer Backup Time Drives UPS Innovation
home automation devices — rely directly on AC power. To protect such equipment from power surges and brownouts, it’s important for an uninterruptible power supply (UPS) system to be included in the installation. An important trend in UPS systems is greater use of exter- nal battery packs.
U
A typical UPS system has a built-in battery that also pro- vides backup power, but often the backup power only lasts for 15 minutes or so, notes Bill Allen, director of marketing for Carrollton, Texas-based Para Systems, which manufac- tures UPS systems under the Minuteman brand. “We’re seeing a focus on longer battery backup times,” Allen says.
Security dealers can address this need by using larger UPS systems but Allen says, “A more elegant solution would be to provide a UPS with external battery pack capability.”
CENTRAL STATIONS’ UNIQUE POWER REQUIREMENTS Nowhere is backup power more important than for the central station responsible for monitoring thousands of accounts. For optimum backup protection, central stations may opt to use a UPS that is backed up by a generator. When selecting a UPS, central station decision-makers should make sure to purchase a line-interactive system, advises Allen. A line interactive UPS constantly monitors voltage at the input, boosting or reducing it to keep it at a steady output. Systems that are not line interactive solve power problems by going to the battery, which can shorten battery life, Allen says. Another option is to use an online UPS that uses a DC conversion process to regulate the system, which Allen says is “the safest and most secure but more expensive.” The UPS, which is so critical to central station power backup, creates some specific requirements for any gen- erator installed to back it up. UPS systems put particular demands on generator sets because they are non-linear in nature, according to Gary Olson, director of technical support with Minneapolis-based manufacturer Cummins Power Generation. “Non-linear loads distort the voltage waveform of a generator, and require use of good voltage regulation equipment for proper operation. This is par- ticularly true for generators rated less than 200 kW, which often are supplied as standard with less expensive and
84 October 2010
nlike low-voltage fire and intrusion systems, some other types of security equipment — including the computing equipment in the central station, as well as some video and
capable voltage regulators. For non-linear loads, you need a voltage regulator that is three-phase sensing (assuming you have three-phase power), full wave rectification, pulse width modulation, and an independent power supply, such as a permanent magnet generator.”
Olson also advises that the National Electrical Code recently was modified to include requirements for facilities that are deemed by authorities as “critical infrastructure.” When this occurs, data centers and other facilities must meet installation and performance requirements that are the same as more traditional critical facilities like hospi- tals. There are many specific requirements that can add significant cost to a facility, but result in a considerably more reliable power supply for the facility. So, it’s critical that an owner be aware of the requirements prior to con- struction planning. One piece of good news is that new generator sets are
available with excellent sound attenuation equipment and will include engines that exhaust less than 10 percent of the harmful contaminants that they have in the past. Some areas of the country that suffer from poor air quality will have even stricter requirements starting in 2011. Most manufacturers can meet these requirements, but at significant added cost. “You won’t see the black smoke from the diesel engine that you have seen in the past,” comments Olson. “It’s getting to the point that you can almost breathe the exhaust. You won’t see it and probably won’t even smell it.” ■
Power Supply Tips
Allen Forman, president of Brooklyn, N.Y.-based power supply manufacturer Altronix Corporation offers these tips for installing and servicing power supplies:
1. Assure that power supplies are easily accessible with ample room for stand-by batteries and cable management.
2. Determine the physical location and proximity to the security equipment and the appropriate wire gauge required.
3. Make sure there is appropriate ventilation when installing rack mount power supplies and that any outdoor power supplies will operate in the prevailing temperature ranges and conditions.
4. Make sure power supplies are installed in compli- ance with specific building code requirements under the auspices of the authority having jurisdiction.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156 |
Page 157 |
Page 158 |
Page 159 |
Page 160 |
Page 161 |
Page 162 |
Page 163 |
Page 164 |
Page 165 |
Page 166 |
Page 167 |
Page 168 |
Page 169 |
Page 170 |
Page 171 |
Page 172 |
Page 173 |
Page 174 |
Page 175 |
Page 176 |
Page 177 |
Page 178 |
Page 179 |
Page 180