One of the problems of long runtime applications is that they require, of course, a large battery bank. Following an outage it’s the UPS’ job to recharge this battery bank. When specifying a UPS much effort is put into ensuring you are going to get x minutes or hours of runtime for your particular load – but what about recharging that battery? How long will that take?
A typical charger in a UPS will deliver around 1Amp maximum. If you think about it, this means that in one hour you can deliver 1 Ampere Hours worth of capacity into the battery. If you have a battery string consisting of 9Ah blocks, then you can expect the battery to be recharged in around 9 hours.
A battery does not charge in a linear fashion. As the battery becomes more charged it takes more time to add further charge to it.
But what if you added some more battery strings to this, another string would make the recharge 18hours, another, 27 hours etc. Now this is for an ideal charging situation. In reality, the charging efficiency tapers as the battery approaches full charge, so the time to recharge is in excess of this.
In long runtime applications this can be problematic. In the event of a long outage you may have to wait for several days before the batteries are in a condition to be relied on again. This clearly can be an unacceptable situation. The only way around this, is to either reduce the battery capacity and hence your runtime, or increase the charging current.
Our new VFI6000BL meets this need. It has an adjustable battery string voltage making it configurable for different battery configurations and has six times the charge current of a standard unit at 6A. This means you can add battery capacities up to 100Ah and achieve recharge times in under a day. Connect this to our B16 cab and you can achieve 2 hours runtime for a 5000W load.
What’s more the UPS unit is rack mountable, or can be free standing, for maximum configurability, if that’s a word. If used in vertical orientation, the LCD can be rotated to assist viewing.
The unit has a high output factor of 0.9, giving 5400W of true power capability, making it ideal for high powered server applications. Being 6KVA it is a hardwired unit, both input and output, but 2x10A IEC320 C14 outlets are provided for added convenience.
Further features include the ability to parallel units together for enhanced capacity or redundancy, Emergency Power Off (EPO) connector, an Intelligent Slot for advanced SNMP communications or a relay card, and serial communications via USB or RS232.
Great post.